Add a call out to arping whenever an IP is assigned to the public interface (happens on CC failover, instance restoration, and elastic IP assignment).  Th\
e callout broadcasts an unsolicit
ed ARP message to the network which should cause servers/network devices on that network to flush and renew their ARP caches for the assigned IP.

    Fixes: EUCA-2973 EUCA-3450
add a timewait after arping call, with a comment to evaluate whether to wait() at all
Merge branch 'maint/3.2/testing' into dev/nurmi/euca-2973
Merge branch 'maint/3.2/testing' of git.eucalyptus-systems.com:eucalyptus into dev/juphoff/euca-2973
Merge branch 'maint/3.2/testing' of git.eucalyptus-systems.com:eucalyptus into dev/juphoff/euca-2973
Merge branch 'maint/3.2/testing' of git.eucalyptus-systems.com:eucalyptus into dev/juphoff/euca-2973
Merge branch 'maint/3.2/testing' of git.eucalyptus-systems.com:eucalyptus into dev/juphoff/euca-2973