CMFileManager: update German translation

Patch Set 1:	* Fix some typos
		* Shorten some strings
		* Change some strings to be easier to understand

Patch Set 2:	* Change strings regarding the comments

Patch Set 3:	* Change strings to fit better in line
		http://files.jackmu95.de/files/cyanogenmod/screenshots/CMFileManager_genaeral_settings_German.png

Change-Id: I64b6be6e6b8e8be74ced8fe62139207ec0558089