Consider separating Terraform/Cloud-Sandbox deployment into separate repo

[mwengren]

Related to better defining the workflow for Cloud Sandbox end users to access the platform, we discussed in meetings the idea of separating out the Terraform and deployment or infrastructure-related code into a separate repo.

This would allow new users to have a simplified version of the user-facing code deployed automatically to their home directories when they log into the Sandbox environment.

TBD: what portions of this repo belong in a new Terraform/infrastructure repo and what belongs in user home environments.