This enables alpha blending for both font_outline and
font_outline_punch_through.
I have also experimented more with 16-gray vs 256-gray--I have not
decided which between monochrome, 16-gray, or 256-gray I like the
most.
Perhaps a better test might be to test hanzi.
This fully threads both the real minimum size of the texture and the
dimensions of the texture through to the TA parameters.
This also removes spurious zero-area drawing commands (space
characters).
This still needs to be cleaned up, particularly to properly pass the
texture size around--there are a few unnecessary '128x256' magic
numbers scattered in the code.
