Added a file for putting in global utility functions
Imported new code files
added level id argument to the debug stuff
Made new parent class for building and powerplant
Added constants for building revenue
Added code for building revenue
Added coin resource
Added code for varied building spawn time and count
clever code re-organizing
Powerplant now inherites entity
Removed debug printing
Moved out global function
Render coins on buildings with revenue
Merges
merged master in