PASS Pilot - add modularization

[cyork]

[derekbelrose]

The goal with this project is to modularize PASS so that an instance is as simple as possible.

When this is complete, it should be simple to deploy a new instance/tenant for PASS.

For each instance, the main.tf would normally be several thousand lines of code. With modularized setups, we just include the pass/infrastructure module and provide variables required. This reduces the amount of work to 20-30 lines per environment.

My 10000 ft tasks are:
Take the Shared infrastructure and make any reference to JHU a variable
Move the terraform files into a shared module
Repeat for environment specific infrastructure (this is the lion's share of the work)