make index.html template pass the W3C validator: http://validator.w3.org

#2668
check wifi/IP/webserver in onResume() to react to changes when running

If Kerplapp is running, and the user switches away to change to the same
wifi AP that another Kerplapp user is running, then Kerplapp should update
itself when the user returns to Kerplapp.

I suppose Kerplapp should also receive broadcasts about network state
changes so it reacts a bit more pro-actively.
symlink index.html in repo/ dir, in case the user browses there

Just to make it idiot proof, make the local repo show the index.html all
over the place so that whatever URL the user goes to, they get the
bootstrapping page.

closes #2668
move repo into standard user repo path: /fdroid/repo

refs #2685