Adding the beginnings of a calendar view.  Primitive table iterating over weekdays and dance classes.  Need to separate out calendar functions from the index view functions in the js and possibly extract out the filters in the view.
Arranging dance classes in the appropriate (start_time, weekday) location on the grid, using the proper time zone.
Separate Dance Class and Calendar Controllers with filters in application.js.  We'll start with this and move to a better place for things that are duplicated such as the filters.