FEATURE: add database table for Courses

[r0ckwav3]

Part of Epic: #6

Create a database schema for courses (possibly inspired by Organic)

For this schema create:

• An Entity class
• A Repository class
• A Controller class
• A Database migration

Verify that the endpoints are visible on swagger and the database is visible on the dokku postgres.

[r0ckwav3]

Schema, based on organic:

• long id (autogenerated)
• string code
• string name
• string term

example object: { id: 1 code: "CMPSC 156" name: "Advanced Application Development" term: "F24" }

[r0ckwav3]

other potential design question is whether to have a start + end date. The commons already have their own and syncing up might be difficult. Also I'm not sure what the CSV for a course looks like, so I'll probably try to get that info before merging this