update the mailing list address used to report bugs in nfs-utils.
Removed the BUGS section in the mount.nfs and umount.nfs man pages since
they weren't consistent with the contents of the BUGS sections in others
in nfs-utils.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Steve Dickson <steved@redhat.com>