[docs] [issue20265] Bring Windows docs up to date

Kathleen Weaver added the comment: Could we make this a separate issue, and I will work on it next?

From #20265:

The faq doesn't mention the new launcher for Windows. Rather than write too much I'd simply cross reference this http://docs.python.org/3/using/windows.html#python-launcher-for-windows. I think this also impacts on the section "How do I make Python scripts executable?". ---------- _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue20265> _______________________________________