Image optimization, file type correction, fixed execute permissions

* Optimized images for great justice!
* buddycloud.png 100x100 is actually a JPEG.
* Removed executable bit from nonexecutables.

### File size reductions
Total change -159764
<table>
<tr><th>Size change</th><th>File path</th></tr>
<tr><td>-6376</td><td>assets/img/free-100/cryptocoin.png</td></tr>
<tr><td>-3235</td><td>assets/img/free-100/surespot.png</td></tr>
<tr><td>-1652</td><td>assets/img/free-100/git-annex.png</td></tr>
<tr><td>-1458</td><td>assets/img/free-100/etherpad.png</td></tr>
<tr><td>-1432</td><td>assets/ico/apple-touch-icon-144-precomposed.png</td></tr>
<tr><td>-1404</td><td>assets/img/free-100/zenphoto.png</td></tr>
<tr><td>-1391</td><td>assets/img/free/lorea.png</td></tr>
<tr><td>-1390</td><td>assets/ico/apple-touch-icon-114-precomposed.png</td></tr>
<tr><td>-1372</td><td>assets/img/free-100/movim.png</td></tr>
<tr><td>-1365</td><td>assets/img/free/mumble.png</td></tr>
<tr><td>-1365</td><td>assets/img/free/tails.png</td></tr>
<tr><td>-1362</td><td>assets/img/free/cryptocoin.png</td></tr>
<tr><td>-1350</td><td>assets/img/free-100/opennic.png</td></tr>
<tr><td>-1303</td><td>assets/img/free-100/tentio.png</td></tr>
<tr><td>-1292</td><td>assets/img/free/etherpad.png</td></tr>
<tr><td>-1283</td><td>assets/img/free/opennic.png</td></tr>
<tr><td>-1272</td><td>assets/img/prop/ios.png</td></tr>
<tr><td>-1261</td><td>assets/img/free-100/diaspora.png</td></tr>
<tr><td>-1261</td><td>assets/img/prop/ms-bing.png</td></tr>
<tr><td>-1253</td><td>assets/ico/apple-touch-icon-72-precomposed.png</td></tr>
<tr><td>-1243</td><td>assets/img/free/zenphoto.png</td></tr>
<tr><td>-1236</td><td>assets/img/prop/bing.png</td></tr>
<tr><td>-1220</td><td>assets/img/prop/ms-windows.png</td></tr>
<tr><td>-1200</td><td>assets/img/free/movim.png</td></tr>
<tr><td>-1191</td><td>assets/img/free-100/mumble.png</td></tr>
<tr><td>-1184</td><td>assets/img/prop/whatsapp.png</td></tr>
<tr><td>-1176</td><td>assets/ico/apple-touch-icon-57-precomposed.png</td></tr>
<tr><td>-1172</td><td>assets/img/prop/apple.png</td></tr>
<tr><td>-1164</td><td>assets/img/prop/aim.png</td></tr>
<tr><td>-1136</td><td>assets/img/prop/ms-ie.png</td></tr>
<tr><td>-1131</td><td>assets/img/free/tentio.png</td></tr>
<tr><td>-1130</td><td>assets/img/free/diaspora.png</td></tr>
<tr><td>-1128</td><td>assets/img/prop/google-drive.png</td></tr>
<tr><td>-1116</td><td>assets/img/free/i2p.png</td></tr>
<tr><td>-1112</td><td>assets/img/prop/tumblr.png</td></tr>
<tr><td>-1102</td><td>assets/img/prop/flickr.png</td></tr>
<tr><td>-1101</td><td>assets/img/free-100/lorea.png</td></tr>
<tr><td>-1094</td><td>assets/ico/favicon-retina.png</td></tr>
<tr><td>-1093</td><td>assets/img/prop/apple-messages.png</td></tr>
<tr><td>-1091</td><td>assets/img/prop/google-youtube.png</td></tr>
<tr><td>-1087</td><td>assets/img/prop/ms-skydrive.png</td></tr>
<tr><td>-1086</td><td>assets/img/prop/google-chrome.png</td></tr>
<tr><td>-1073</td><td>assets/img/prop/ms-outlook.png</td></tr>
<tr><td>-1069</td><td>assets/img/prop/dropbox.png</td></tr>
<tr><td>-1065</td><td>assets/img/prop/yahoo.png</td></tr>
<tr><td>-1055</td><td>assets/img/prop/google-mail.png</td></tr>
<tr><td>-1055</td><td>assets/img/prop/google-plus.png</td></tr>
<tr><td>-1051</td><td>assets/img/free-100/riseup.png</td></tr>
<tr><td>-1048</td><td>assets/img/free/piwik.png</td></tr>
<tr><td>-1034</td><td>assets/img/prop/facetime.png</td></tr>
<tr><td>-1028</td><td>assets/img/free-100/tails.png</td></tr>
<tr><td>-1027</td><td>assets/ico/favicon.png</td></tr>
<tr><td>-1026</td><td>assets/img/prop/paypal.png</td></tr>
<tr><td>-1021</td><td>assets/img/free/replicant.png</td></tr>
<tr><td>-1018</td><td>assets/img/prop/ms-skype.png</td></tr>
<tr><td>-1013</td><td>assets/img/free/piwigo.png</td></tr>
<tr><td>-1013</td><td>assets/img/free/riseup.png</td></tr>
<tr><td>-1008</td><td>assets/img/prop/google.png</td></tr>
<tr><td>-1000</td><td>assets/img/prop/linkedin.png</td></tr>
<tr><td>-994</td><td>assets/img/free/git-annex.png</td></tr>
<tr><td>-981</td><td>assets/img/prop/twitter.png</td></tr>
<tr><td>-980</td><td>assets/img/free/friendica.png</td></tr>
<tr><td>-970</td><td>assets/img/prop/zoho.png</td></tr>
<tr><td>-969</td><td>assets/img/free-100/fedora.png</td></tr>
<tr><td>-969</td><td>assets/img/prop/ms-office.png</td></tr>
<tr><td>-963</td><td>assets/img/free-100/csipsimple.png</td></tr>
<tr><td>-960</td><td>assets/img/free-100/tahoe-lafs.png</td></tr>
<tr><td>-954</td><td>assets/img/prop/apple-safari.png</td></tr>
<tr><td>-953</td><td>assets/img/free/fn.png</td></tr>
<tr><td>-950</td><td>assets/img/free/seafile.png</td></tr>
<tr><td>-949</td><td>assets/img/free/redphone.png</td></tr>
<tr><td>-942</td><td>assets/img/prop/instagram.png</td></tr>
<tr><td>-941</td><td>assets/img/prop/facebook.png</td></tr>
<tr><td>-938</td><td>assets/img/prop/android.png</td></tr>
<tr><td>-936</td><td>assets/img/free/tahoe-lafs.png</td></tr>
<tr><td>-930</td><td>assets/img/free/textsecure.png</td></tr>
<tr><td>-923</td><td>assets/img/prop/whatsapp-android.png</td></tr>
<tr><td>-922</td><td>assets/img/free/nightweb.png</td></tr>
<tr><td>-922</td><td>assets/img/prop/apple-icloud.png</td></tr>
<tr><td>-903</td><td>assets/img/free/syndie.png</td></tr>
<tr><td>-900</td><td>assets/img/free/orbot.png</td></tr>
<tr><td>-891</td><td>assets/img/free/bitmessage.png</td></tr>
<tr><td>-884</td><td>assets/img/prop/apple-osx.png</td></tr>
<tr><td>-872</td><td>assets/img/free/csipsimple.png</td></tr>
<tr><td>-872</td><td>assets/img/free/fdroid.png</td></tr>
<tr><td>-869</td><td>assets/img/free/cyanogenmod.png</td></tr>
<tr><td>-866</td><td>assets/img/free/surespot.png</td></tr>
<tr><td>-860</td><td>assets/img/free/xabber.png</td></tr>
<tr><td>-857</td><td>assets/img/free-100/i2p.png</td></tr>
<tr><td>-854</td><td>assets/img/free/gnupg.png</td></tr>
<tr><td>-854</td><td>assets/img/free/mediagoblin.png</td></tr>
<tr><td>-846</td><td>assets/img/free/autistici.png</td></tr>
<tr><td>-844</td><td>assets/img/free/adblockedge.png</td></tr>
<tr><td>-842</td><td>assets/img/free/owncloud.png</td></tr>
<tr><td>-839</td><td>assets/img/free/debian.png</td></tr>
<tr><td>-839</td><td>assets/img/free/salutatoi.png</td></tr>
<tr><td>-839</td><td>assets/img/free/sparkleshare.png</td></tr>
<tr><td>-833</td><td>assets/img/free/gibberbot.png</td></tr>
<tr><td>-827</td><td>assets/img/free/seeks.png</td></tr>
<tr><td>-817</td><td>assets/img/free/cryptocat.png</td></tr>
<tr><td>-813</td><td>assets/img/free-100/syndie.png</td></tr>
<tr><td>-809</td><td>assets/img/free-100/piwigo.png</td></tr>
<tr><td>-803</td><td>assets/img/free/prohibition.png</td></tr>
<tr><td>-797</td><td>assets/img/free/jitsi.png</td></tr>
<tr><td>-797</td><td>assets/img/free/linphone.png</td></tr>
<tr><td>-791</td><td>assets/img/free/chatsecure.png</td></tr>
<tr><td>-789</td><td>assets/img/free/adium.png</td></tr>
<tr><td>-787</td><td>assets/img/free/httpseverywhere.png</td></tr>
<tr><td>-785</td><td>assets/img/free/disconnect.png</td></tr>
<tr><td>-781</td><td>assets/img/free/pumpio.png</td></tr>
<tr><td>-779</td><td>assets/img/free/tor.png</td></tr>
<tr><td>-774</td><td>assets/img/free/gnusocial.png</td></tr>
<tr><td>-768</td><td>assets/img/free-100/friendica.png</td></tr>
<tr><td>-766</td><td>assets/img/free-100/piwik.png</td></tr>
<tr><td>-762</td><td>assets/img/free/evolution.png</td></tr>
<tr><td>-760</td><td>assets/img/free/otr.png</td></tr>
<tr><td>-757</td><td>assets/img/free/fedora.png</td></tr>
<tr><td>-753</td><td>assets/img/free-100/replicant.png</td></tr>
<tr><td>-746</td><td>assets/img/free/firefox.png</td></tr>
<tr><td>-730</td><td>assets/img/free/yacy.png</td></tr>
<tr><td>-726</td><td>assets/img/free-100/fdroid.png</td></tr>
<tr><td>-721</td><td>assets/img/free-100/seafile.png</td></tr>
<tr><td>-719</td><td>assets/img/free/fixtracking.png</td></tr>
<tr><td>-705</td><td>assets/img/free/duckduckgo.png</td></tr>
<tr><td>-696</td><td>assets/img/free/pidgin.png</td></tr>
<tr><td>-690</td><td>assets/img/free/namecoin.png</td></tr>
<tr><td>-687</td><td>assets/img/free-100/gnusocial.png</td></tr>
<tr><td>-679</td><td>assets/img/free/bsd.png</td></tr>
<tr><td>-679</td><td>assets/img/free/enigmail.png</td></tr>
<tr><td>-667</td><td>assets/img/free-100/owncloud.png</td></tr>
<tr><td>-656</td><td>assets/img/free-100/redphone.png</td></tr>
<tr><td>-655</td><td>assets/img/free/clawsmail.png</td></tr>
<tr><td>-650</td><td>assets/img/free/linux.png</td></tr>
<tr><td>-647</td><td>assets/img/free/openstreetmap.png</td></tr>
<tr><td>-645</td><td>assets/img/free/startpage.png</td></tr>
<tr><td>-641</td><td>assets/img/free/buddycloud.png</td></tr>
<tr><td>-635</td><td>assets/img/free-100/prohibition.png</td></tr>
<tr><td>-634</td><td>assets/img/free-100/cyanogenmod.png</td></tr>
<tr><td>-624</td><td>assets/img/free/thunderbird.png</td></tr>
<tr><td>-611</td><td>assets/img/free/trisquel.png</td></tr>
<tr><td>-606</td><td>assets/img/free/webpg.png</td></tr>
<tr><td>-602</td><td>assets/img/free/ethercalc.png</td></tr>
<tr><td>-598</td><td>assets/img/free-100/cryptocat.png</td></tr>
<tr><td>-597</td><td>assets/img/free/kmail.png</td></tr>
<tr><td>-582</td><td>assets/img/free-100/textsecure.png</td></tr>
<tr><td>-575</td><td>assets/img/free/icecat.png</td></tr>
<tr><td>-566</td><td>assets/img/free/mailvelope.png</td></tr>
<tr><td>-548</td><td>assets/img/free-100/orbot.png</td></tr>
<tr><td>-548</td><td>assets/img/free/retroshare.png</td></tr>
<tr><td>-527</td><td>assets/img/free/bitcoin.png</td></tr>
<tr><td>-525</td><td>assets/img/free/wordpress.png</td></tr>
<tr><td>-520</td><td>assets/img/free-100/fn.png</td></tr>
<tr><td>-511</td><td>assets/img/free/noscript.png</td></tr>
<tr><td>-502</td><td>assets/img/free-100/nightweb.png</td></tr>
<tr><td>-483</td><td>assets/img/free/liberte.png</td></tr>
<tr><td>-465</td><td>assets/img/free-100/gibberbot.png</td></tr>
<tr><td>-465</td><td>assets/img/free/icedove.png</td></tr>
<tr><td>-463</td><td>assets/img/free/onionbrowser.png</td></tr>
<tr><td>-443</td><td>assets/img/free-100/mediagoblin.png</td></tr>
<tr><td>-436</td><td>assets/img/free-100/salutatoi.png</td></tr>
<tr><td>-422</td><td>assets/img/free-100/gnupg.png</td></tr>
<tr><td>-361</td><td>assets/img/free-100/sparkleshare.png</td></tr>
<tr><td>-356</td><td>assets/img/free/noblogs.png</td></tr>
<tr><td>-354</td><td>assets/img/free-100/evolution.png</td></tr>
<tr><td>-351</td><td>assets/img/free-100/chatsecure.png</td></tr>
<tr><td>-348</td><td>assets/img/free-100/linphone.png</td></tr>
<tr><td>-342</td><td>assets/img/free-100/xabber.png</td></tr>
<tr><td>-318</td><td>assets/img/free-100/pumpio.png</td></tr>
<tr><td>-307</td><td>assets/img/prop/groupwise.png</td></tr>
<tr><td>-278</td><td>assets/img/free-100/duckduckgo.png</td></tr>
<tr><td>-276</td><td>assets/img/prop/google-picasa.png</td></tr>
<tr><td>-275</td><td>assets/img/free-100/httpseverywhere.png</td></tr>
<tr><td>-268</td><td>assets/img/free-100/adium.png</td></tr>
<tr><td>-264</td><td>assets/img/free-100/jitsi.png</td></tr>
<tr><td>-231</td><td>assets/img/free-100/firefox.png</td></tr>
<tr><td>-224</td><td>assets/img/prop/google-play.png</td></tr>
<tr><td>-220</td><td>assets/img/free-100/ubuntu.png</td></tr>
<tr><td>-219</td><td>assets/img/free-100/tormail.png</td></tr>
<tr><td>-181</td><td>assets/img/free-100/pidgin.png</td></tr>
<tr><td>-169</td><td>assets/img/free/linuxmint.png</td></tr>
<tr><td>-164</td><td>assets/img/free-100/fixtracking.png</td></tr>
<tr><td>-138</td><td>assets/img/free-100/bitmessage.png</td></tr>
<tr><td>-125</td><td>assets/img/free-100/namecoin.png</td></tr>
<tr><td>-108</td><td>assets/img/free/tormail.png</td></tr>
<tr><td>-61</td><td>assets/img/free-100/debian.png</td></tr>
</table>