windows .pro file improvements and version change to 0.6.4.5

  - Add vars to more easily adapt to different drive layouts
  - Reorganize and clean up LIB and INCLUDE vars
  - Actually use Boost lib suffix var
  - Fix qrencode qrcode var names, text, and lib names
  - Add -fpermissive to C/CXXFLAGS to change error on func arg types to warning
Enable build info (build.h) on windows

On windows with command line Git (which includes msys/bash shell) from
http://git-scm.com/
installed, you can successfully execute the genbuild.sh script to create
build.h. Use USE_BUILD_INFO=1 to enable on any host/OS. No checking for
git is done, so it will fail if Git is not installed on windows.