README: Update download links
README: Add windows screenshot
Update Russian translation
Merge branch 'pr476'
Linux: Do not link with rtmp, tbb, gnutls, avfilter

We really just don't need those rigth now, as lintian helpfully pointed out
Fix ChatForm::onAvMediaChange not checking callId/friendId

May help with #458
Update link for os x binary
OS X icon support
Merge branch 'pr480'
Merge branch 'pr481'
Debian: Depend on libstdc++-6 >= 4.8.2 not >= 4.9