Add Snake Man level
Add more rooms to Snake Man
More work on snake man
Kill player if he falls through the floor
Snake man updates
Fix camera scrolling behavior

Made camera scrolling behavior work like it does in Mega Man 3. The
camera pans left or right when Rock passes through the mid-line of the
screen. You can be offset and it will still follow you, but it won't
auto-center. It now only moves when Rock moves a full pixel so this
should make things look nice and crisp as it moves.
Merge pull request #222 from zackthehuman/master

Fix camera movement, more work on Snake Man