In Kubernetes 1.2 we used template PersistentVolume for provisioning. When a
claim for dynamic volume was detected, Kubernetes did:
- create template PV for the claim with dummy pointer to storage asset
- allocate storage asset such as AWS EBS
- fill real pointer to the created storage asset to the template PV

In refactored volume provisioner, Kubernetes allocates the storage asset first
and then creates a Kubernetes PV instance already with the correct pointer
to the storage asset.

To support seamles upgrade from 1.2 to 1.3 we need to remove these
unprovisioned template PVs. The new controller does not use them, it will see
PVC for dynamic provisioning and create real PV instead.