Disable PlayersSource due python-dbus bug :(

For some reason, python-dbus dbus.SessionBus.get_session().list_names() (as get_players_uri does) crash if called at PlayersSource.get_items
And isn't a exception, this crash python interpreter and kupfer dies quickly
Options:
1 - :'(, and wait until someone fix this
2 - Try call this at plugin load (maybe work) downside require restart to scan player
3 - Use 'command-line', downside require command that does it
4 - Use other dbus implementation, downside (more dependencies)
5 - Rewrite anything having fun with it...