Correctly add and remove machine and container tokens including their committed state.
Merge pull request #367 from huwshimi/update-tokens

This branch adds and removes container tokens and sets the committed states on tokens.

QA:
- drag two services to the canvas
- open the machine view
- drag one of the unplaced units to "Create new machine"
- a machine "new0" should have been created and should have a blue background
- click on "new0" and the bare metal container should be visible in the container column
- drag the second unplaced unit to "Create new container"
- a new container "new0/lxc/new1" should have been created with a blue backround
- click "deploy" and then "confirm"
- the "new0" machine should be removed and replaced with a new machine "0" without the blue background
- the "new0/lxc/new1" contaier should be removed and replaced with a new container "0/xc/o" without the blue background