Added:
- LabeledControlSet: a utility UI element to group labeled map controls into a nice-looking table form
- Map event handling calls
- Utility method to retrieve layer specs from a ServerRenderedMapLayer
Addressing Nathan's comments on my last checkin:
- Fixed main.js such that the demo page (map.html) works
- Removed some unnecessary code
- Modified comments
Fix some minor issues with this branch - formatting, an extra comma, and allowing for layers that don't have names