Cells & Layers Refactor!

+ added cachebuster to the script loader
~ converted cell containers into layers
- removed duplicated layer drawing
+ added generic layer drawer
~ renamed background square JIT loader to be more explicit
~ renamed,refactored, and moved the "getHighest" method to Load
|_ * throws TypeException if cell at coordinates doesn't exist in any layer.  Probably a bad decision.
~ Mouse and Info use the Load(er) to get the top layer at their coordinates