Support MongoDB targets

Background

MongoDB is one of the most widely used NoSQL databases today. I'm quite interested in Warpgate's design philosophy and would love to see support for MongoDB targets: reusing Warpgate's existing user authentication and target assignment capabilities to proxy the MongoDB protocol, allowing clients to transparently access backend instances while reusing the existing session management and auditing mechanisms.

Desired Features

Protocol proxy: Clients connect to MongoDB through Warpgate without modifying connection settings or installing extra software. Authentication & target assignment: Reuse the existing authentication flow and target assignment policies.