Added explicit version to Docker images
Modified Docker image mountable folders to better facilitate addition of custom Cayley config files AND data persistence
Added data-only container to fig.yml. Also added custom Cayley config file.
Added data-only container to fig.yml. Also added custom Cayley config file.
Updated README with fig.yml data-only containers and custom-config volume mounts.
Changed Cayley logging to stderr ONLY.
Merge pull request #2 from saidimu/dev

Persistent data, custom configs and stderr logging