We have seen users interpret the current output ('Complete') of
'server migrate --wait' as if it meant success as well and be surprised
when later they learned that the migration was complete and failed.
This change adds a pointer to the that output, how to actually check the
success/failure of a migration, hoping to eliminate this user confusion.
Change-Id: I09030705a39405366d6202a5ac743cc4d1ddd63c
bbe686109d