Update Docker installation documentation

[christophermaier]

The Docker installation documentation is outdated (refers to 0.10.0, doesn't mention docker-compose-override.yml or how to use that, etc.)

Installation

• Update Docker installation copy reference to 0.13.0
• Update Docker link to 0.13.0

Cog with Docker (http://docs.operable.io/docs/cog-with-docker-compose)

• Update to match Installation page + consider making this an installation process from the installation. (Deleted page)

Time to update!

Related: #905

[Shelton]

Updated Docs so that there were more distinct sections. Will ask the community soon about their thoughts on our current installation.

[Shelton]

• @kevsmith will update the docs to reflect the correct references to the docker-compose.yaml
• hid the page that referenced Cog with docker-compose