Adding Keystone environment variables to NBI

Adding the necessary environment variables to the
NBI MDG Dockerfile in order for the Keystone authentication
to work.

Completing the docker-compose yaml, fixing renaming typo
in keystone dockerfile and updating environment file
creation.

Change-Id: I4eb15119f4dba304494ef16fc90eea8d8c230927
Signed-off-by: Eduardo Sousa <esousa@whitestack.com>