Add UI for deleting responses

Adds ability to delete selected records in the dashboard

This is a fairly large changeset

Structural changes:
* Updates Backbone to 1.0.0
* Starts a pattern of breaking views out atomically and linking them to external html templates. 
* Starts a pattern of creating more self-contained views that don't need to know anything about their parent 

Known bug: deleting an item on the dashboard does not remove it from the map. That's because we're no longer keeping track of layers by ID. That's a larger fix I'm working on  now, and too much for this pull.