Added mapping from scaling types to scaling function implementations
Rendering data is applied in draw-function.
Added 'scaling' API.
Fixed bar rendering.
Configure scaling for bar plot track
Scaling configuration is passed as an object.
Added 'category_totals' function.
Changed parameter and field names
Updated test code
Implemented track that displays ticks and coordinates for coding regions.
Updated test code to include tick track.
Heuristic for number of ticks in region
processFlatArray and doLayoutForViewport take location field accessor as parameter
Updated test code