Moved cover art settings to their own submenu
Added support for multiple urls for cover art.
Added future support for local cover art
Added a non working local cover art provider
Cover art providers now have a name
Multiple cover art providers are now supported
Added permission for local cache
Completed sdcard cache
Cover helper can now read from local FS
Cached cover now checks if file exists before returning it to the helper
No more static methods
Covers are now saved into cache if enabled
Added helpful debug info
Tweaked cover storage quality a little

Cache now uses less SD Card space
Local covert art can now search multiple filenames
Added default music path value
Added filename support for cover art (closes #170)
Fix cast bug
Fix multiples / in urls.
Removed useless methods
Merge branch 'refs/heads/coverart'

Conflicts:
	MPDroid/res/values-fr/strings.xml