support for Tiled levels

Currently doesn't work right, but I wanted to put something on GitHub,
so you guys can take a look at it. Not sure what the problem is, maybe
something to do with the viewport or camera or something. I feel like
I'm close though.
Added sprites for all monsters.

I think I messed up on my original copy of Mike's first commits. I'm
working on my own fork now, but I am not sure how to get back to the
main branch.
debugging for level

fixed a bug I made with the GetBounds method. added way to manually
change player position. Messed around in the draw method as well but its
still only drawing a small square of the map, in what looks like the
wrong place.
fixed camera, better manual player movement

Accidently left a line that was setting the camera position before
drawing the map.
Commenting player.update made it easier to move. When the player goes
off screen that is the edge of what the level should be.
Fixed drawing map and collision

Got it to work, finally. I'll have to clean it up cause there's still a
lot of debugging stuff and commented code, but that should be trivial.
Added enemy and sprites
Merged with Tom's level code.