Pause: convert MRect to SDL_Rect.
Players: convert MRect to SDL_Rect.
Score: convert MRect to SDL_Rect.
Tutorial: convert MRect to SDL_Rect.
Tweak: convert MRect to SDL_Rect.
Victory: convert MRect to SDL_Rect.
Zap: convert MRect to SDL_Rect.
Vectorize Icon.

Some of the shading still needs work, particularly on the leftmost eye.
Add high(er) resolution icon renders.
SDLU: delete code marked as SDL BUG that seems to be unnecessary.

Hopefully I will not have to revert this.
SDLU: Add missing void to argumentless functions.

And rect can be const in SDLU_InitSurface.
MTypes: delete.
Fix all of the syntax errors I introduced.

The code now compiles, but there are numerous graphical glitches
(sadly, this is not particularly surprising).

Known broken things:
- Falling blobs on menu screen aren't erased.
- Playing field is wrong in pretty much every way possible.
- Speech bubbles in tutorial are wrong size/position.
- Floating combo score isn't erased.

Things that seem to be ok (surprisingly):
- The pause menu.
- The opponent, level, punishment and score boxes.
- High scores.