In the original `mongo` image maintained by Docker, you could create a new user using the environment variables MONGO_INITDB_ROOT_USERNAME and MONGO_INITDB_ROOT_PASSWORD.

As we all know, MONGO can be pejorative, and we try to remove it from all official documentation.

Would it be possible to create aliases for these environment variables so that MONGO_INITDB_ROOT_USERNAME and MONGODB_INITDB_ROOT_USERNAME would both work (same for PASSWORD)?

This way, we would support the syntax from the original Docker-maintained image, but our documentation could start to show `MONGODB_INITDB_ROOT_USERNAME`.

Tagging ryan.egesdahl@mongodb.com, as we discussed earlier.