Update models.py
Revert "Update models.py"

This reverts commit 3781a2a1fb3bf8eade5426fe1bb8ac90c8921940.
Added the CourseFeedback model to the student app
Changed charfields to textfield where appropriate and set max length in time_length
Added base to course foreign key
Add extra multiple choice options to course feedback model and add titles to textfields in course feedback model
Change encourage questions to be a multiple choice field with options yes and no instead of a boolean
Merge pull request #3 from calblueprint/course_feedback_model

Course feedback model
Add MEDIA_ROOT to settings.py
Fix all bugs on models.py
add blank=True to additional_info field
Merge pull request #5 from calblueprint/byron/course_model

Byron/course model
fix merge error