named pipes for win32

[totaam]

Split from #389 where an old patch can be found.

[totaam]

Mostly done in r12219:

• xpra list works
• xpra version / info sort-of-work

TODO:

• the client sometimes exits before processing the packet because the pipe has been closed by the server - this should be handled as an EOF instead
• use the "socket-dir" as named pipe path? (currently hard-coded to Xpra\)
• use the "socket-dirs" as the list of named pipe paths we search?
• shadow server crashes easily with debug logging (could be the same issue as win32 shadow server crashes with bind-tcp and -d sound,gstreamer #1149)

[totaam]

2016-04-18 10:29:47: antoine uploaded file named-pipes-mess.patch (6.9 KiB)

experimenting with tweaks to make named pipes work properly - hard

[totaam]

This will do for 0.17, will follow up in #1174.

As it is, we can start a server and query it, ie:

xpra_cmd shadow

From another window:

xpra_cmd info

(or xpra_cmd version, etc..)