bpo-38133: Allow py.exe launcher to locate installations from the Microsoft Store (GH-16025)

(cherry picked from commit ed93a88)

Co-authored-by: Steve Dower <steve.dower@python.org>

Author: miss-islington

Misc/NEWS.d/next/Windows/2019-09-12-12-05-55.bpo-38133.yFeRGS.rst

@@ -0,0 +1,2 @@
+Allow py.exe launcher to locate installations from the Microsoft Store and
+improve display of active virtual environments.