'swfStage' gets set to 'stage' in updategraphicsmode() but... that does
absolutely nothing, because they both contain exactly the same thing.
And these variables aren't referenced anywhere else. So I'm removing
both of these variables.
This removes all global args in all functions in titlerender.cpp.
Additionally, all 'dwgfx' has been renamed to 'graphics' in that file
(there are a lot of them, as you might guess).