Adding a simple cluster usage based scaling policy. This will serve as an example to add
more complex auto scaling policies in the future.
Merge pull request #3 from rjnagal/scaler0

Adding a cluster usage based scaling policy.
Add new deps for GCE metadata.
Add ability to add instances via cloudprovider.

Adds the interface and makes it not implemented in all components except
GCE. Implements adding instances in GCE.
Merge pull request #4 from vmarmol/master

Add ability to add instances via cloudprovider
Add new deps for GCE metadata.
Add ability to add instances via cloudprovider.

Adds the interface and makes it not implemented in all components except
GCE. Implements adding instances in GCE.
Adding provisioner service.

Service initially only exposes one endpoint:

/instances

Sending a POST to this endpoint requests the creation of a set of
instances.