Consolidate pass-auth and pass-docker reverse proxy functionality into pass-core

[markpatton]

What?

The PASS API should be easy to deploy and it should be easy to understand how authentication is handled. In order to do that, pass-core should take over the functionality of pass-auth and the pass-docker reverse proxy. The pass-docker environments will also need to updated.

Why?

The current pass-docker architecture is complicated interleaving a reverse proxy, pass-auth, and pass-core. Instead pass-core should take over that functionality. See https://docs.google.com/document/d/1swYRvwNeouMyuG9xEbSBLFffUpBstllI1bP5Zcsx3ME/edit?usp=sharing for more information.

How?

See the above linked document for information on what routes pass-auth and the reverse proxy currently handle and what pass-core needs to do. Spring security has support for SAML 2 which should help with the pass-auth functionality.

Acceptance Criteria

The pass-docker environments should be updated such that they can run the new pass-core. Show that Shib integration works on staging.

Related Issues

Blocking #907, #908, #909

[markpatton]

The major changes are the removal of pass-auth and the reverse proxy from pass-docker. Instead pass-core takes on those roles and handles SAML authentication as well as requests for pass-ui under /app/.

[markpatton]

Closing after testing on stage.