Preshow

[tom enos]

Using an empty dict for the preshow causes Keyerror: 'transitions'
So an empty preshow needs to be a {"transitions":[]}, but that is not a great solution for the config. I suggest adding a test in configuration_manager.py for an empty dict() and then setting it correctly.

line 118 in configuration_manager.py

                preshow = json.loads(_LIGHTSHOW_CONFIG['preshow_configuration'])

change it to

                temp = json.loads(_LIGHTSHOW_CONFIG['preshow_configuration']) 
                if temp:
                    preshow = temp

and that should fix it as line 87 and 88 are

        preshow = dict()
        preshow['transitions'] = []