Add Programs table and relate it to Services.

A Program has many Services.
Add CRUD support for Programs in admin interface.

Includes the ability to assign a program to a Service.

Other improvements:
- You can now access Organizations, Locations, Services, and Programs from the main screen.

- You can add a new location and a new program from the main screen.

- Reduced duplication in forms.
Merge pull request #255 from codeforamerica/add-programs

Add CRUD support for Programs in admin interface.