! WIP: Levels load only tiles they need.

- removed static_level from Level
+ Added load_around for Level.

! Only read the tiles needed.
Lag from opening texture file? Test this.

x Load all the tiles for a level.
x Draw only one.
Jitters.

+ Load only what's needed for a level.
+ Draw all loaded.
No jitter! Initialization is to blame.

To add... load around for Levels via the World Map.