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.

'''

        up
        |\________
       / \_      /\
      /    \   /   \
   d1        d2    d3


   up has a single output that outputs {d1 : .8, d2:0.1}
   

'''