Use linker comment #pragma and preprocessor for re-exporting stable
API functions and variables.
Module definition file, custom build targets and entry point code
become unnecessary and can be removed.
This change also fixes missing _PyErr_BadInternalCall export on x86.
* Add missing header files to pythoncore.
* Add missing file filters ("Resource Files" in particular) to
all projects.
* Add new sub-filters for private headers in pythoncore and
for 3rd party source files.
* Add missing _zoneinfo configurations in pcbuild.sln.
* Update bdist_wininst with the new zlib location.