Completed Officer Model

Five Model Classes:
1. Officer: inherits from User, has office hours, has classes taken
2. OfficeHour: has day of week, has time of day, associated with officers
3. BerkeleyClass: has class name, associated with officers
4. OfficerHour: used to link Officer with OfficeHour (through for ManyToManyField)
5. OfficerClass: used to link Officer with BerkeleyClass (through for ManyToManyField)

Admin Registrations:
1. Officer: information, can add office hours, can add classes taken
2. OfficeHour: can add day/time
3. BerkeleyClass: can add class name
Merge remote-tracking branch 'upstream/master' into officer-model
Merge pull request #2 from upenu/officer-model

Completed Officer Model