core:Add support for apc_snmp power management...

Add support for apc_snmp power management agent

fence_apc is not supporting apc firmware 5.x
In order to test apc firmware 5.x agents, we will have to use
fence_apc_snmp

Change-Id: I7a80a787db453e612b844d55fc05d6530b6b92ad
Signed-off-by: Eli Mesika <emesika@redhat.com>
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=916570