Standardize document and Issue Labels

[A1Liu]

TODO from docs/contributors/getting_started.md

[Bad-Science]

Thanks for opening this! This is actually pretty much done, I just haven't added it to the docs. See the yacs repo labels for more info.

[A1Liu]

Yeah, I copy-pasted them into the docs in #20 , I didn't add the html styling but I can probs add that without too much trouble