When the filesystem /etc lives on is completely full, umount will exit
    with exit status 16 if the umount syscall succeeded but it was unable to write
    a new mtab file because the disk is full. umount won't exit with status 16
    under any other circumstances.
    
    This patch changes the fs.sh, clusterfs.sh, and netfs.sh resource agents
    to check treat both exit status 0 and exit status 16 as success.
    
    Resolves: rhbz#819595
    
    Acked-by: Lon Hohberger <lhh@redhat.com>
    Signed-off-by: Ryan McCabe <rmccabe@redhat.com>