This patch is adding a new evaluator for the alarms of type
'loadbalancer_member_health' which evaluates the alarm by checking
the operating status of the members in a given load balancer pool.
A new config option 'member_creation_time' is introduced in order to
ignore the members in initialization status.
This is the first part of the auto-healing solution.
Change-Id: I57b848e6dc6aa5e79af1c17dbf1a42a9f068f174