core: fixing a missing fencing audit log message

This patch fixes the message to the audit log where the Host is set to Connecting state.

The patches addresses
1) fix the audit log key from VDS_HOST_IN_CONNECTING_STATE which had no
message to VDS_HOST_NOT_RESPONDING_CONNECTING
2) add a flood rate to this audit log such that it will not logged in
each network exception event
3) fix a minor issue in the regular engine log ( ${1} => {1} )

Change-Id: I33b683664a33fa27df283e0abc448eb6564b678e
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1070674
Signed-off-by: Eli Mesika <emesika@redhat.com>