Add optional parameters to rally container to register a deployment

When using Rally docker image, a container is created, then database needs to be created manually and then OpenStack deployment must be registered (also manually).
The proposal is to automate the creation of the database, and automate the registration of an existing OpenStack deployment in Rally so that container is really ready to use as soon as container is up.
This can be done by passing deployment information as optional parameters of the container – Either from environment variables or passing JSON file (to be consistent with current Rally flow).

If no deployment parameters are passed, container will be created as it is created today otherwise container will have Rally with a deployment registered and ready to start testing (Adding usability/omitting some manual steps).