keyboardcomposer destroy fix and cleanups - We were destroying KeyboardComposer a little too much. Fortunately, we weren't passing the right number of arguments, so this was merely an error. - About the TODO comment removed: we don't need to use combine_dict since Submaster logic will be changed entirely when we/if we move to a SubServer world and keyboard composer will not be the wiser.

# Abstract UI widgets

class UI(Something):
    pass

class Scale(UI):
    def __init__(self, start, stop, res=0.001):
        pass

""" unfinished
class Button(UI):
    def __init__(self, etc)
"""