[windows] fix portaudio compilation, enforce a better _WIN32 pre-processor flags
[waf] fixing linker problems for MSVS builds
[windows] getops splitted into c/h files
[windows] regex.h removed, the regex in DriverLoader now ifdefed
between posix/windows platform
[WIP] repairing MSVC build with waf
[windows] remove inline assembly for atomic incrementer and
decrementer
[windows] change posix-getops with a lib that's also portable for
MSVC
[waf] add linker flags and build-ignores to make sure windows
compiles
[common] many ifdefs for windows, most notably unistd.h removal

This driver is very similar to the JackNetDriver, but instead of connecting
through the network, it connects to its upstream server through standard jack
API. So it can only reach local servers which must be running as the same user
or in promiscuous mode.

The main use case is the multi-user, multi-session, shared workstation:

 - a classic server with hw driver is launched system-wide at boot time, in
   promiscuous mode, optionaly restricted to the audio group
 - in each user session, a jackdbus server is automatically started with
   JackProxyDriver as master driver, automatically connected to the
   system-wide one
 - optionaly, each user run PulseAudio with a pulse-jack bridge