Include info from Victor's "Build CPython on Windows"

[ned-deily]

We should consider including the info in @vstinner 's quick guide to building Python on Windows into the "Getting Started" chapter of the devguide.

https://cpython-core-tutorial.readthedocs.io/en/latest/build_cpython_windows.html

[Mariatta]

GitMate.io thinks possibly related issues are #267 (Cannot build devguide in virtual environment on Windows), #90 (Windows build instructions out-dated/unclear for 2.7 branch), python/core-workflow#113 (Questions about cherry-picker from Windows never-venv user), python/core-workflow#46 (Drop the gcc build from Travis), and #172 (Add PDF build).