[FEATURE] Implementing Support for Minors in Schedule + Sidebar

[KobeZ123]

Issue Summary:
This is a large ticket that can be broken down into various smaller ones but the idea is that we want to implement support for minors on GraduateNU

Acceptance Criteria:
There are several pieces to this effort:

1. Adding scraped minors and creating the endpoints to serve information about the minors
2. Look into how plans are currently saved and allow a minor to be saved alongside the plan
3. Updating the Add and Edit plan modal to enable creation of plans with minors specified (design here)
4. Updating the sidebar to allow swapping between view for major and minor requirements (design here)