Clean-up related to move from openedx -> edx

[robrap]

ADR 0001 was written from the openedx perspective while this repo while still part of openedx. Now that it has been deprecated on the openedx side, and forked to the edx org for edx.org only purposes, some changes are required to clean up this repo.

Action items:

• ADR related changes
  • Add note to https://github.com/edx/edx-documentation/blob/38aed32acf3ee9a2b902400f92df824e8aa7be8a/decisions/0001-develop-documentation-translation-process.rst noting it has been superseded by an new ADR. Make the note obvious.
  • Add a new ADR with an changes now that this repo is for edx.org readthedocs.
  • Update README.rst as appropriate to make it more from the edx.org side.
• Remove books that are not built as part of edx.org. (@jristau1984 - maybe you can supply a list?)
• Clean-up openedx specific code and config. See example.
• What else no longer belongs? Community focused (Tutor, OpenCraft, etc. notes and config).
• If it doesn’t already, the README (or something) should explain about docs.edx.org and that edx.readthedocs.org is from the edX project with subprojects, etc.
• why does https://edx.readthedocs.io/projects/devdata/en/latest/ have the openedx logo?

[jristau1984]

[UPDATED]:

• The edx-analytics-pipeline docs are way out-of-date from a styling perspective (e.g. old logo, etc.).
• According to this github search, the only reference to these docs are from an old archived version of devstack.
  • If we are going to keep building its docs, someone could at least link to them from the README in https://github.com/edx/edx-analytics-pipeline.
• The readthedocs link might be referenced from a bunch of Confluence wiki pages though.

[robrap]

The "edx" project has two parts:

• It builds edx/edx-documentation.
• It has a big list of subprojects, which doesn't do anything other than make each subproject available under edx.readthdocs.org.
  • That said, https://edx.readthedocs.org/projects/edx-toggles/en/latest/ currently redirects to the openedx docs, so I'm guessing that Axim wants that to remain in place and for us not to remove the openedx projects.
  • The openedx projects makes the edx subproject list more cluttered on our side, but we'll survive.