* upstream/develop:
Remove whitespace hack on empty post content
Change output directory of fontello
add html-webpack-plugin to karma config
use another fork of fontello-webpack-plugin
add animate-spin class
remove needless code
use another approach for versioning font files
versioning the font resources through webpack
fix "can't find property of undefined" errors in mrf transparency panel
move mention button right next to mute button
restore muted users collapsing logic on other user’s profiles