Support for PlaylistId flashvars

In this branch I've added support for kpl{index}Id flashvars instead of kpl{index}Name and kpl{index}Url flashvars.

Also I've cleaned up KalturaPlaylistHandeler.
And refactored playlistResult object to include playlists name

Please review & merge
Notice that because of caching bug in master, I've disabled the cache for playlists.

Thanks,
Ran.