This attempts to improve Visual Studio builds by:
Fixing builds especially when introspection builds are not done and when
python.exe is in the
PATH. This moves where we set up the default value for
$(PYTYHON) in the NMake Makefiles so that it can be consumed for all builds, and also add a similar setup for
PERL, so that they can be called by the NMake Makefiles directly when they are in the
PATH, or can be in-turn called when their full paths are passed into the NMake command line via
Add support for building ARM64 Windows binaries in the NMake Makefiles.
With blessings, thank you!