vos: remaddrs sub-command

vos: remaddrs sub-command

Introduce the vos remaddrs sub-command for removing multi-homed server
entries from the vldb.  The remaddrs sub-command completes the listaddrs
and setaddrs command suite and allows vos changeaddr to be deprecated
completely.

Change-Id: I98e92e776a153591a617a5b04037c3b6139d4732
Reviewed-on: http://gerrit.openafs.org/11606
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Chas Williams <3chas3@gmail.com>
Reviewed-by: Daria Brashear <shadow@your-file-system.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>