Added y-axis screen scrolling

for the ground and dungeon
Made the sprite a little skinny to fit in little holes
MAPS UPDATED
Changed the origins for each level

Now screen scroll works in all levels (yes, even 9-1)
Greatly simplified the scrolling logic

With tables!
Added Clouds band and Catacombs
OK Screen Scrolling!

I haven't implemented the upper atmosphere yet because I don't have
double jump etc
Merge pull request #11 from variousauthors/screen_scrolling

Screen scrolling