CMFileManager: Update German translation

Patch Set 1:	* rename strings
		* unify translations
		* some cleanup

Patch Set 2:	* rename Dateimanager to Datei Manager

Patch Set 3:	* make it reviewable
		  layout will be fixed if it's ready to merge

Patch Set 4-7:	* revert some changes
		* rename/shorten some strings
		* add missing translations
		  http://review.cyanogenmod.org/#/c/29840/

Patch Set 8:	* final cleanup
		* fix formatting

Change-Id: I7cfd366e21c80bbaef2454c79c5c998e8a7b12c4