Update the docs

[jennifer-bowser]

This should be the last ticket in the epic

[jsstevenson]

A few TODO's here

• Trim down storage option pages as needed
• Once updated docker-compose is available, replace quick start instructions with a description of how to use it
• Move UTA/seqrepo pages to external repos (either directly to their own repos or to a centralized biocommons location)

[korikuzma]

Not sure if we plan to cut all (or some of the readme), but should probably update references to files.

For example:

• anyvar/README.md

  Line 71 in c1e2ccc

  AnyVar supports PostgreSQL databases. [Configure PostgreSQL for AnyVar.](docs/postgres.md)

  - should we be linking to RTD instead of RST file?

• anyvar/README.md

  Line 119 in c1e2ccc

  - `ANYVAR_TEST_STORAGE_URI` - This specifies the database to use for tests. If you set up a postgres database by following the README-pg guide suggested in step 1, then you can just copy/paste the example `ANYVAR_TEST_STORAGE_URI` found below.

  - would be nice to link to the README-pg guide

[jsstevenson]

Not sure if we plan to cut all (or some of the readme), but should probably update references to files.

Yeah ideally the readme should be approximately a browser window long imo -- header material, useful links, a quick example, etc. As much as possible, we should only describe how to do something once.