Add LARC tutorials as sections

[EricPedley]

This seems tough because we're gonna have to scrape the LARC site since it's server-side rendered (https://enroll.larc.uci.edu). We might want to split this change up between us and PeterPortal API since the backend stuff is more their domain.

As for the frontend, I'm thinking maybe we have a toggle in the search menu to show LARC tutorials, and if it's toggled on, the LARC tutorials show up inline next to the lectures and discussions in the search results and behave just like any other section. This will be easier to pull off once we merge the TypeScript rewrite and the fields necessary for a section are well-defined.