Update _head.twig

Remove googlefonts now called in font.css - need still to put the woff file in font directory
Update font.css

Add reference for ptsans font in local instead of google fonts
add font file
Merge pull request #473 from nsteinmetz/dev

Baggy Theme - PtSans font is now local
[add] message in install screen to prevent user when wallabag is already installed
Merge remote-tracking branch 'upstream/dev' into dev
a lot of refactoring: tag action is now handled by home view and uses sorting and pagination. Some small view enhacenments. Fix of #476, #461 for baggy and other themes