Adds deletion of alarms in case exception is thrown during scaling config

If a exception is thrown during the configuration of a scaling group, POL
will check if there have been alarms created through MON, and if that is
the case, it will delete them.
Also, it adds validation of the MON alarm responses. It throws an exception
if MON returns status: False, meaning there was an error creating the alarm.

Signed-off-by: Benjamin Diaz <bdiaz@whitestack.com>
Change-Id: I4f5f0c95ae2cce0c71efb73ff2e06cdf8ea08864