Fill out ReadTheDocs page/Generated Docs

[DannyWeitekamp]

We need a read the docs (or similar style) page. That has:

• Installation instructions
• Descriptions of the agent API
• Descriptions of each agent
• Descriptions of each planner
• Descriptions of at least Operator implementations we plan on using going forward
• Descriptions of each learning mechanism type
• Descriptions of each learning mechanism implementation
• Descriptions of useful internal utilities like StateMultiView

There seems to be some start to auto documenting AL, but I don't know if this has reach the point of actually generating a document.
Update: yes it has started but needs to be filled out

[eharpste]

We have auto generating docs for each repo already: https://al-core.readthedocs.io/en/latest/ The install instructions are lifted straight from the repo's README. We can start putting doc comments in code for the functional API docs but if you want things outside of that we need to make individual rst files and add them to the toc.