Add hierarchies

[putmantime]

Refactored igests to use individual hierarchies from Regenstrief. Refactored CLI Updated Readme

[putmantime]

@joeflack4 This PR has more than intended with all the docs. The main changes relevant to our discussion are:

• code_ingest.py
• part_ingest.py
• build.py
• README.md
• data/part_files/*
• data/owl_files/*