vgrename renames a VG.

All VGs visible to a system need to have different names, otherwise many
LVM commands will refuse to run or give warning messages. VGs with the
same name can occur when disks are moved between machines, or filters are
changed. If a newly connected disk has a VG with the same name as the VG
containing the root filesystem, the machine may not boot correctly. When
two VGs have the same name, the VG UUID can be used in place of the source
VG name.
