Create central repository of models

[gussmith23]

We should have a repository (either a folder in this repo or a standalone) that holds all of our models. Ideally it would have:

• A python module that has functions for each model, where each function runs through the entire import process (e.g. from Pytorch)
• Relay plaintext versions of the models (maybe)
  • If so, then include tests in CI that check that the relay versions == the imported versions

Might be a good one for @vcanumalla