Merge pull request #42 from BU-CS673/graphics

Graphics -> Production
Merge pull request #74 from BU-CS673/production

Production
Merge pull request #76 from BU-CS673/backend

Backend
started creating sprint1 integration test

Lots of broken things -- help, Chris!
Integration test is partially working

- Need to fix Sprites.create overload hack
- grass sprites are being drawn in the wrong location
Refactored World.addEntity and Sprite.createSprite

- Also fixed many tests
Fixed remaining integration loop problem

The test itself had a problem: the inner loop incremented i, which is
the counter for the outer loop.
Fixed conflicts
Merge pull request #80 from BU-CS673/sprint1Integration

Sprint1Integration -> Canfield