autogenerate items in site/reference.md from python code

[ericbuckley]

Summary

Update doc build process to dynamically generate values on the reference page from source code.

Acceptance Criteria

• A module to support autogenerating features and their descriptions (from docstrings)
• A module to support autogenerating blocking keys and their descriptions (from docstrings)
• A module to support autogenerating matching functions and their descriptions (from docstrings)
• Update to the build docs process to add results from the above modules into the markdown

Dependencies

#112