Z-Wave: ZXT-120 Fix non-unicode chars in database

Ooops - should never copy and paste from Google translate!
Also removed the SWITCH_ALL command class as its not required and not
used in the ZXT-120 - although the manual states its a supported class -
it doesn't actually implement it.
Merge pull request #1507 from wezhunter/zwave-fix-zxt120

Z-Wave: ZXT-120 Fix non-unicode chars in device xml