Feature - courses
<!-- Make sure the title starts with "Feature - [insert short description of feature]" -->
## Description
A new class should be added to the models: Courses.
Courses should maintain a list of assignments associated with that course, and users that are associated with the course.
A controller should be created that handles anything to do with courses.
## Priority - High
This is important to make the tool more usable.
## Definition of done
- When courses can be created
- When assignments can be added to a course
- When users can be added to a course
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issue