Preceptor Form Updates, closes #2, #4, #5, #6.

**Preceptor Changes**
- Added example to degree field
- Added example `Other-Support.doc` to Other Support field
- Rank is now only editable by administrator and changed to dropdown with choices `Associate Preceptor` and `Full Preceptor`
- Added Biosketch and Curriculum Vitae to preceptor file uploads