Python/mkdocs init

[alexluck-sift]

Adds mkdocs to the project for building documentation.

• Implements mike for documentation versioning.
• Created github actions for deploying docs to Github pages. Each new version deployed to pypi will generate a new doc version, but only major.minor.patch formatted versions are visible in the drop down. The PATCH portion of the version is omitted from the docs version.
• PRs will be published as doc versions, but hidden. Upon PR closure, old PR doc versions should be cleaned up.
• Hidden doc versions can be accessed via direct links.

Docs branch
The gh-pages branch contains the Github pages content.

The python folder contains all doc versions. In the future, we may publish documentation for different client libraries by publishing them to other root folders in the repo.

VIEW THE DOCS

[ian-sift]

seems solid and we can always iterate on nitty-gritty later. just a few minor questions and comments.