update to 0.31.2
    
    - refer to $local_fs instead of $localfs in the init script (#802719)
    - install a systemd unit file instead of an init script on still-in-development
      releases (#820137,818963)
    - build binaries position-independent and marked for earliest-possible symbol
      resolution (#852800)
    - don't worry about moving things from /usr to / when they're the same (#852800)