Enable volume and mount functionality

This commit enables the following functionality:
* Specify dataVolumes when creating a contianer to have Docker create data
volumes.
* Specify dataVolumesFrom when creating a container to mount the volumes
from the specified container in the container you're creating.
* Represent Docker data volumes inside the Rancher API as volumes and
mounts. A volume represents a volume from the host's perspective and a
mount describes the association between a volume and an instance.
Merge pull request #10 from cjellick/volumes-and-mounts

Enable volume and mount functionality
Add container execute action
Add host-api to pyagent
Serve UI from CDN
Console agent v0.2.1
Merge pull request #11 from ibuildthecloud/add-exec

Add container execute action
Merge pull request #12 from ibuildthecloud/add-host-api

Add host api
Merge pull request #13 from ibuildthecloud/add-ui

Add ui
Merge pull request #15 from ibuildthecloud/console-agent-version

Console agent version
Implement mount volume lifecycle

* Remove, restore and delete a mount when it's instance transition
through a corresponding process.
* Allow volumes to be deleted and actually perform the delete on disk
(when appropriate)