Add a device operational state of RECONCILING and update code

When the Core sends a reconcile request to an adapter for a given device then the Core will set the operational state of that device to RECONCILING. Upon a successful reconciliation of that device, the adapter will set the operational state of that device to its current operational state.

When a device is in RECONCILING state, no operations on that device is allowed, other than the delete operation and operational/connection state changes from the adapter as part of the reconcile process.