Handle pipes on platforms where they are non-existant of broken.

Handle pipes on platforms where they are non-existant of broken.
We do this by creating a TCP socket pair instead of a normal pipe. Since
Windows isn't UNIX-y enough to support read()/write() on sockets, we also
need a wrapper to handle read() vs recv() and write() vs send().

git-svn-id: file:///home/lennart/svn/public/pulseaudio/trunk@840 fefdeb5f-60dc-0310-8127-8f9354f1896f