Document global auto option related funtions with comments...

Add a Proxy driver

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

This wrapper driver has the same usage as its parent JackWaitThreadedDriver,
but for non-threaded (callback) drivers. After waiting for Initialize to
return, its main thread simply ends instead of calling the driver's Process
method in a loop. The decorated driver, which must extends JackRestarerDriver
instead of JackWaiterDriver, can restart the wait cycle by calling its
RestartWait method.

This makes it possible to use JackWaitThreadedDriver as a base class
for a non-threaded version.

Mingw waf fixes

The mmsystem.h header check didn't include windows.h so check fails even though mmsystem.h was present.

No biggie, but since this is C++, let's use the C++ includes.

Partial merge from pr/77

Setting the JACK_NO_AUDIO_RESERVATION environment variable let one skip
the audio reservation bits.

Indentation fix from smiszym

Correct date/version ordering in jackd.1

Doxygen fixes, less hardcoding and --htmldir

Auto options and removed automagic dependencies

(the AutoOption class takes care of defining env['SAMPLERATE'] and HAVE_SAMPLERATE)

(drop conf.define('HAVE_CELT', ...) since the AutoOption class handles this)