Implement new output format flow

[rael346]

This PR essentially addresses #4 by

• Adding new extensions to the save files to denote stages of the major (see the enum SaveStage)
  • initial will be always be the newest scraped majors
  • staging will be the version that the commit version is based of off when using Tooling to check
  • commit will be the version of majors that are used by Graduate in prod
• Have a specific flow when scraping a major (in classify.ts)
  • When a new major's html is fetched from the catalog, it will be checked against the staging.html of that major
  • If that major doesn't exist, then that major will continue to be tokenized and parsed in the initial stage
  • If that major does exist and the staging version is different from the fetch one, then the major will continue as initial stage
  • If that major does exist and the staging version is the same, then the major will continue with the staging version

A few items that arose during this ticket that should be addressed in a latter one:

• The degrees folder should be outside of the major-scraper repo, since it might be better to make this an option in #5
• Fix the failing tests and have one for #10 (will probably be its own PR after this one)
• Have a way to just run the scraper on a single major through the command line
• Better error logging for the parser