Added information to README.md.
Added event handling code.
Added ability to add service layer.
Added button to clear service area.
Merge pull request #7 from WSDOT-GIS/service-area

User can now select and remove a service area.
Legends are now incorporated into layer chooser.
Modified CSS to hide elements of layer chooser.
Now hiding minority sublayers.
Merged in changes from master.
ChartDataProvider now uses a single feature layer URL. This URL is retrieved from the Web Map.