Light theme searchbar fixed. Fixes #485
Fix wrong String.format call in Search's Add toast. Fixes #486
Cover art path configuration description text specifies that absolute URLs are accepted. Fixes #484

Added "New" suffix to the string so that translators notice the change. Commented out the old translations.
Add a setting to choose what artist tag is used for Artist list population. Closes #482

Handling libraries is hard. It's even harder when everybody has their own needs and ways of managing their library.

The removal of this setting has been controversial, but the old situation wasn't perfect either.
The setting now allow you to use the "artist" tag, "albumartist" or both.
There can be potential implications on the album list that follows an artist selection (since I don't propagate this option to AlbumsFragment), but since I'm not really sure how to approach this I'll address it (if needed : "both" is a great option for albums in my opinion) later.
Cache users are not affected by album handling since it works great anyway.
Reindent settings
widgets: Convert to UNIX line endings.
widgets: Remove duplicated code between widgets.
widgets: Fix a few java docbook warnings.
widgets: Remove unused individual widget updating.

Remove it for now, readd if it becomes useful in the future.