Implement database storage for the composite container API

State changes of the composite containers should be stored in a database. A database is necessary to ensure a distinctive name, store state information, and provide diagnostics.

The unique identifier of the composite container should be stored.
The composite container descriptor should be converted to YAML and stored.
The composite container descriptor should be decomposed and stored as individual items.
The states of each container in the composite container should be stored in the decomposed area and may be "SCHEDULING, LOADING, RESTARTING, TERMINATING, and TERMINATED'

scheduling = magnum is sorting out where to put the container
loading = magnum is loading the images into docker
restarting = magnum detected a failure of the container and is restarting
terminating = magnum is terminating the container
terminated = magnum has terminated the container