The Windows build now depends on Python 3.6 to fetch externals, but it
will be downloaded via NuGet (which is downloaded via PowerShell) if it
is not available via `py -3.6`. This means the only thing that must be
installed on a modern Windows box to do a full build of CPython with all
extensions is Visual Studio.
Cherry-picked from 51599e2bdd, parts of 40a23e8899, parts of 68d663cf85, d5cd21d75a, and possibly others that I've missed.
Also:
* Rename db -> bsddb for disambiguity
* Update sqlite3 to 3.14.2.0 since it's the version we use on 3.x, and it's simpler to just use it than to also upload the old version to cpython-source-deps
* Add PCbuild/*.ilk to .gitignore
* Silence warnings caused by duplicated defines from Modules\expat\winconfig.h
* Add WIN32 define to VS9.0 project files to match MSBuild project files.
The old project files move to PC/VS9.0 and remain supported.
VS2008 is still required to build 2.7; VS2010 (or later, plus Windows SDK 7.1)
is *also* required to use the new project files.
Anselm Kruis
Zachary Ware
Jeremy Kloth