Cleanup and improve updateXBMCSet, updateXBMCGenreMovie, GetMovieGenres.

The main improvement is special characters (quotes etc) are now properly,
encoded so they don't break JSON.
Forgot to comment out debugging code in last commit (b1d59e2)
 Small fix, getSelections() returns an array of records not values.
Merge pull request #33 from fyfe/fix-save-sets-genres

Cleanup and improve updateXBMCSet, updateXBMCGenreMovie, GetMovieGenres.