Merge pull request #5 from DF1E/master

update german
Operations can now be interrupted. Fixed OperationsService notifications.
Changed MediaStoreUtils copy, rename and move logic. Changed MediaStoreUtilsTest. The test is not completed yet.
Disabled MODIFY observer events that can cause deadlock on some devices firing continuous events on the same directory.
Removed Bundle creation when sending FileObserver events to Handler.
Refactored some code and fixed some issues.
Fixed operation dialog issues. Bumped gradle tools version.
Replaced xml characters with UTF characters.
Symlink icons updated.
Replaced String.format calls after getQuantityString() with getQuantityString formatting
Renamed icons according to Android icon naming conventions. Added white notification icon.
Renamed attrs according to new icon names.
Replaced notification icon with the one generated by Android Asset Studio.
Added proper nullable-Shell handling. ActionBarIconMonitoredActivity now shows a real icon.
Added ActionBar-PullToRefresh with fixes.
Added more PullToRefresh header decorView fixes.
ShellHolder now re-asks for superuser if Settings.su is enabled every 5 calls.
Removed unused method.
Update README.md
Reamed PureFM*Utils to PFM*Utils. Added FileObserverNotifier that fires the observer events (used for places where there are no permissions for default FileObserver events). getCanonicalPath() of CommandLineFile now resolves path by CommandReadlink.