REwritten chunk generation a bit.. theres a framework for multiple lines though I can't make it work.

Chunk generation now returns an object with a "master" and "platform" attributes. MAster contains points tobe added to the master line, "platform" currently contains nothing but will contain points to generate a platform
Merge branch 'master' of https://github.com/brdunfield/GGJ2014

Conflicts:
	chunkGenerator.js