[BUG]: Proxy issues keys for unregistered developers

[fogfish]

The issue_key always issues key even it developer is not registered. The correct behaviour is to fail with 404 or bad request.

curl -vvv localhost:4001/plugins/auth_key/issue_key \
   -H 'Content-Type: application/json' \
   -d '{"developer_id": "d8d63fd0-3987-48dc-9ac2-2f2f5fe49e92"}'

[phanimahesh]

It is a bug, the implementation is incomplete. I would prefer 400 bad request since the route exists, it's the payload that is nonsensical.

A check to verify that the developer id exists should be sufficient to fix this.

In addition to verifying that the developer exists, we should also verify that the request is from the same developer. Control api will take care of the authentication and make it available on the connection as metadata. I'll write up a proposal on what data will be made available and how it is expected to be accessed.