Update documentation for 2022, including contributing and master/2022 build process

[dylancashman]

The VIS22 Web chairs need to provide an updated contributing guide that we can point the whole group to. Similarly, we also need to document the tricky things relating to the branching structure: some updates (i.e. /index.html) will only get picked up from the master branch, while most will only be picked up in the respective year's branch (i.e. vis2021, vis2022).

[dylancashman]

Might want to update internal documentation at https://docs.google.com/document/d/1Yi1l6Vz92ZcB5dvCqrC1F49280OOPgkh6IwrVK7XwO0/edit#heading=h.lkx8zj6edpir and then put other documentation on the CONTRIBUTING.md file in the repo.

[yelper]

Just in case: http://ieeevis.org/year/2022/info/contributing