bpo-9566: Fix some Windows x64 compiler warnings (#2492)

bpo-9566: Fix some Windows x64 compiler warnings (#2492)

* bpo-9566: Silence liblzma warnings

* bpo-9566: Silence tcl warnings

* bpo-9566: Silence tk warnings

* bpo-9566: Silence tix warnings

* bpo-9566: Fix some library warnings

* bpo-9566: Fix msvcrtmodule.c warnings

* bpo-9566: Silence _bz2 warnings

* bpo-9566: Fixed some _ssl warnings

* bpo-9566: Fix _msi warnings

* bpo-9566: Silence _ctypes warnings

* Revert "bpo-9566: Fixed some _ssl warnings"

This reverts commit a639001c949ba53338a9ee047d2ec1efd2505e6f.

* bpo-9566: Also consider NULL as a possible error in HANDLE_return_converter

* bpo-9566: whitespace fixes