Spark History Server REST API missing an environment endpoint per application

The WebUI for the Spark History Server has the Environment tab that allows you to view the Environment for that job.
With Runtime , Spark properties...etc.

How about adding an endpoint to the REST API that looks and points to this environment tab for that application?

/applications/[app-id]/environment

Added Docs too so that we can spawn a subsequent Documentation addition to get it included in the API.