Check that citydata exists for aggregation before displaying
Allow ordering of indicators by value
Allow paginate Indicators by page_size param
Add legend for indicator map page

Update oti-legend directive with style param, allows
    either 'flat' or 'stacked' style

Dynamically create legend max/min values from indicator values

Add OTIMapStyleService:
    Has stubs for future functionality, like custom legends
    per indicator type

TODO: Send CartoCSS style for each indicator to windshaft from angular
      BLOCKED on scala geom fix
Add basic auth to rest_framework
Merge pull request #314 from WorldBank-Transport/feature/auto-load-canned-data

Add basic auth to rest_framework
Merge pull request #311 from WorldBank-Transport/feature/indicator-legend

Feature/indicator legend
Add Dwell Time performance indicator
Rename files and classes to reflect proper indicators
Add indicator for traveltime performance
Type signed and commented code more heavily
Do or do not, there is no try
Break code into multiple lines for readablity
Fix extra indentation