Moved obsolete Wix installer into Experimental branch. NSIS installer moved one level up. Now it supports new build directory structure, does not require to be copied into it and can be built using packaging/winx86/Makefile.cmd or as a qmake-generated "installer" target (using "make installer"). NOTE: this target will NOT be built automatically, you have to build it yourself.
Install system requires Unicode NSIS installer and optionally uses SubWCRev.exe utility (from TortoiseSVN package) to extract some build info from local SVN copy (like revision number, etc.). This info then is available as a properties of installer executable and also used in the installer's executable file name. SubWCRev utility is optional, if it is not found - no extra info will be generated and used.
Also fixed unescaped backslash in openpilotgcs.pri (please check that it does not break !win32 builds).
git-svn-id: svn://svn.openpilot.org/OpenPilot/trunk@2584 ebee16cc-31ac-478f-84a7-5cbb03baadba
