[HOD] Hod should deallocate cluster if there's a problem in writing information to the state file

Consider a scenario where hod runs allocate successfully, but isn't able to save teh allocated information to the clusters.state file. In such a case, it gets an error and exits. But the cluster remains allocated, and unfortunately the user cannot deallocate the cluster now unless he knows the cluster directory.

It is better if HOD can deallocate the cluster in such an error condition.