hide live tv if inapplicable
fixes #42 - Add option for 12h or 24h time format

Add item to prefs screen and change GetTimeString in generalUtils to
use new preference.
Merge pull request #45 from gunnville/master

fixes #42 - Add option for 12h or 24h time format
hide music if inapplicable
Merge pull request #6 from MediaBrowser/master

Update