[multipathd] unix socket daemon control interface

[multipathd] unix socket daemon control interface

The client is wrapped in the daemon.

You can call it through :
- multipathd -k"$cmd" : one shot
- multipathd -k : interactive

The synthax is somewhat rude :/

- lp : list paths
- lm : list maps
- ap $path : add path checker, $path is in the "sdb" form
- rp $path : remove path checker
- am $map : add map event thread, $map is in the "dm-0" form
- rm $map : remove map event thread