update zh_CN translation
Updated Romanian Translation
Updated Romanian translation
Port player and selection bar to GtkActionBar

This also bumps required GTK+ version to 3.12.

https://bugzilla.gnome.org/show_bug.cgi?id=732150
travis: install utopic

Previous commit bumps GTK+ requriement and trusty has 3.10 only
doap category apps
doap: add <programming-language>
self._notification.show() added to the end of _update_track() method.

https://bugzilla.gnome.org/show_bug.cgi?id=734117
notification: don't touch thumbnail outside _on_thumbnail_updated function
window: always go to albums list when we're clicking 'Albums'


https://bugzilla.gnome.org/show_bug.cgi?id=734122
search: always hide Back button when we're showing search results
Updated Basque language
Add HighContrast icons (by Andreas Nilsson)

https://bugzilla.gnome.org/show_bug.cgi?id=734404
Mark two strings as translatable
Updated Hebrew translation
Updated Brazilian Portuguese translation
Updated Assamese translation
search: center results and request 530px width

https://bugzilla.gnome.org/show_bug.cgi?id=734786
Updated Lithuanian translation
Updated Norwegian bokmål translation.