Add "environment_id" and "status" to {hosting_devshop_project_environment} so we can keep environment data even if it is deleted.

Right now if you delete an environment, it will delete the environment record.

Aegir sites and platforms never get "Deleted", so we should maintain this info so old deleted platforms and sites maintain their relationships to the project.

One caveat would be making sure new environments with the same name get proper hosting contexts that don't collide... As long as we check upon environment creation for active environments of the same name, we might be ok... because aegir deletes the records from {hosting_context} when the items are deleted.