German: update translation

Patch set 1: - Add translation for sound-to-vibration conversion toggle
               http://review.cyanogenmod.org/#/c/30379/8

Patch set 2: - Change wording
             - Apply changes made with
               http://review.cyanogenmod.org/#/c/31349/1

Patch set 3: - Another change in wording

Change-Id: Ie4be8ffc3b9cce03cb4a0b0ca12863ef723bfcfa