Kickbox mania

New game mode for kickbox simulation device being developed by Precision Dance Pads.
Substantial changes to the way styles work internally.  Any theme should work the same as before in existing game modes, but probably no theme (except mine of course) works correctly in the new game mode because of the changes to styles. (kickbox game mode requires players to be able to play different styles at the same time, ScreenSelectStyle, ScreenSelectMusic, and OptionRowHandlerListSteps all need their internal handling of styles changed.)
Autogen results for the new game mode haven't been tested, turn mods do nothing.
Notefield positioning and zooming changed to use margin spaces defined by the theme instead of position metrics and a flag in the style.  (NeedsZoomOutWith2Players decapitated)