Update Windshaft to use Indicator API

Windshaft now displays Indicators, rather than test data
URL is:
/tiles/:dbname/:version/:type/:sample_period/:aggregation
Calculate indicator geometry in scala for route aggregations

Geom for an indicator should be calculated with the indicators
themselves, and POSTed to the Indicator API endpoint.

Geom can be an empty string if not relevant.

TODO: Calculate indicator geom for mode aggregations
Update map-controller for new Windshaft API

TODO: Dynamically select indicator URL and refresh layers
based one UI selection