l10n: Arabic update

Localizable.strings: 59% translated

InfoPlist.strings: 66% translated

Settings.bundle: 75% translated

Signed-off-by: Soomin Lee <bubu@mikan.io>

Resources/Settings.bundle/ar.lproj/Root.strings

@@ -96,6 +96,7 @@
 "SETTINGS_MEDIA_LIBRARY_VIDEO_GROUP_PREFIX_LENGTH_EXTRA_LONG" = "Extra long";
 "SETTINGS_SHOW_THUMBNAILS" = "Show video thumbnails";
 "SETTINGS_SHOW_ARTWORKS" = "Show audio artworks";
+"SETTINGS_BACKUP_MEDIA_LIBRARY" = "Include the media library in device backup";
 
 "SETTINGS_FILE_SYNC" = "مزامنة الملفات";
 "SETTINGS_WIFISHARING_IPv6" = "دعم IPv6 لمشاركة الواي فاي";