Clean up/refactor the batch scripts used for building on Windows.
This is mostly a backport of issue #21907, but also includes a few
extras necessary to make the bulidbot scripts as thin as possible.
diff --git a/Tools/buildbot/external-amd64.bat b/Tools/buildbot/external-amd64.bat
index 0ea56b8..13056c7 100644
--- a/Tools/buildbot/external-amd64.bat
+++ b/Tools/buildbot/external-amd64.bat
@@ -1,28 +1,2 @@
-@rem Fetches (and builds if necessary) external dependencies
-
-@rem Assume we start inside the Python source directory
-call "Tools\buildbot\external-common.bat"
-call "%VS100COMNTOOLS%\..\..\VC\vcvarsall.bat" x86_amd64
-
-if not exist tcltk64\bin\tcl86tg.dll (
- cd tcl-8.6.1.0\win
- nmake -f makefile.vc OPTS=symbols MACHINE=AMD64 INSTALLDIR=..\..\tcltk64 clean core shell dlls
- nmake -f makefile.vc OPTS=symbols MACHINE=AMD64 INSTALLDIR=..\..\tcltk64 install-binaries install-libraries
- cd ..\..
-)
-
-if not exist tcltk64\bin\tk86tg.dll (
- cd tk-8.6.1.0\win
- nmake -f makefile.vc OPTS=symbols MACHINE=AMD64 INSTALLDIR=..\..\tcltk64 TCLDIR=..\..\tcl-8.6.1.0 clean
- nmake -f makefile.vc OPTS=symbols MACHINE=AMD64 INSTALLDIR=..\..\tcltk64 TCLDIR=..\..\tcl-8.6.1.0 all
- nmake -f makefile.vc OPTS=symbols MACHINE=AMD64 INSTALLDIR=..\..\tcltk64 TCLDIR=..\..\tcl-8.6.1.0 install-binaries install-libraries
- cd ..\..
-)
-
-if not exist tcltk64\lib\tix8.4.3\tix84g.dll (
- cd tix-8.4.3.4\win
- nmake -f python.mak DEBUG=1 MACHINE=AMD64 TCL_DIR=..\..\tcl-8.6.1.0 TK_DIR=..\..\tk-8.6.1.0 INSTALL_DIR=..\..\tcltk64 clean
- nmake -f python.mak DEBUG=1 MACHINE=AMD64 TCL_DIR=..\..\tcl-8.6.1.0 TK_DIR=..\..\tk-8.6.1.0 INSTALL_DIR=..\..\tcltk64 all
- nmake -f python.mak DEBUG=1 MACHINE=AMD64 TCL_DIR=..\..\tcl-8.6.1.0 TK_DIR=..\..\tk-8.6.1.0 INSTALL_DIR=..\..\tcltk64 install
- cd ..\..
-)
+@echo Please use PCbuild\get_externals.bat instead.
+@"%~dp0..\..\PCbuild\get_externals.bat" %*