Match the cancel orange to the color palette.
Replace attendance screen with an index screen (#14).

- The attendance screen is unnecessary (use attendees).
- Remove the template for the Attendance view.
- Modify controller prev/next logic to use index instead of attendance.
- Add index template.
- Update router to transition fluidly withoutn needing beforeModel.
Remove view reliance on Reservation isAttending* properties.
Remove isAttending* properties on Reservation (#14).

The Contacts table/object will store this state and
it will be computed as needed. There is no reason to
have it on a separate object and screen when it depends
on the Contacts.

- Remove all references to isAttendingBigDay on Reservation object.
- Rmeove all references to isAttendingRehearsalDinner on Reservation object.
Continue work on refactoring out isAttending* (#14).

- Remove all properties using it and reuse.
- Remove any excess code that is not needed.
- Refactor some properties into the baseController.
Finish refactor of RSVP Screens (#14).
> Merge branch 'rsvp-screens-update' into development
Fixes an issue that the Yes/No buttons were not styled properly.

The CSS selector must be more specific in order to override the base CSS. Used Less's nesting for this.

Changed the selected class bindings to be to booleans so I could use Ember's class binding syntax.
Remove console.log from client side javascript.
> Merge branch 'development'