Refine algorithm for map generation and ceiling heights

[PontusAhlin]

Pretty self explanatory, improve the random map generation and add heights for the celings for more immersion / making the map more dynamic.

[williamfridh]

Does this include removing the bars as outer walls?

[alin-but-real]

adding ceilings to everything now

[alin-but-real]

added, now trying to tweak the algorithm for something thats fun but not too wide