More cleaning up fractal demo.

* Separate out 1 VM and 16 VM into separate classes/controls.
* Visually show state of VMs with squares
* Allow squares to be updated outside of start/stop.
* Support common query params on every request in gce.js.
* Have gce.js update UI objects on every status instead of just heartbeats.
* Introduced util.js for some useful string functions.  Changed instance names for fractal to be zero padded so they sort well in UI.