Document Process for creating New PyPI Packages

## Description

As we break out adapters in the [OpenTimelineIO GitHub org](https://github.com/opentimelineio) and drive toward completion of #1386 (rearranging the repos), we'll need each individual adapter to have its own [PyPI](https://pypi.org/) package that can be referenced by the main `opentimelineio` package for "batteries included" installs.

This process should include:

- Naming convention
- Which Users should be added at what permission level
- PyPI API token generation - What user is the token generated as? ([organization support](https://github.com/pypi/warehouse/issues/201) is in progress, but not ready yet)

Having this process documented should make is straightforward for TSC members to create PyPI projects and store secrets on the appropriate repos. This is also good practice to invite others to audit our process and alert us when we may be vulnerable to attack vectors.

Start by reviewing the adapter-repository reorganization described in #1386 and the linked PyPI organization-support discussion. Document the naming convention, user permission levels, API token generation identity, and the appropriate repository secret-storage process; the result is complete when TSC members can create adapter PyPI projects consistently and safely.

Written by the indexing model from the issue text.