ROI controller codes

[joewandy]

The ROI/Grid Controller codes seem a bit messy.

1. Extract ROI generation into its own class, so we can swap between normal or SmartROI
2. Extract scoring into its own class
3. Can also pass in different time exclusion method (e.g. DEW, WeightedDEW) to the scoring calculation
4. Write unit tests to make sure everything still works the same