Factors/Scenario UI with major JS refactor

- Code broken up into modules using requireJS
- Model notification now happens through jQuery event scheduler
- Factors UI are synced to model using events, allows multiple layers
- Full category support (categories that share factors are now linked)
- Load/Reset Scenarios
- Pool model updates requests in weighted overlay to improve responsiveness
- Broke out color-breaks into it's own model (it shares nothing with layers model)
- Removed some dead code
- Added comments