Fix win scons (#359)

* fix a link flag
* another hack to find weirdly named libraries
* Fix handling VCRedistInstall.exe
* add src folders to win-scons include paths
* use path.join
* more weird library suffixes
* fix old python syntax in an SConscript file
* find vcpkg libraries and headers
* add icon dir to windows include paths
* remove non-recursive os.listdir line
* remove bad lib paths
* tools build with env["bits"]
* hard-code vcvarsall.bat path, with a note
* pass in other lib paths
* fix syntax without trying to use f-strings
* more bundled libs on windows
* add bin folders for windows installation to find dlls
* fix CheckLib stuff
* test scons pass X86 correctly
* make 64-bit builds the default for scons
* add package flag for building installers

.github/workflows/scripts/win/scons-build.bat

@@ -1,8 +1,15 @@
 
 setlocal enabledelayedexpansion
 
-for /f "usebackq tokens=*" %%i in (`vswhere -latest -products * -requires Microsoft.VisualStudio.Component.VC.Tools.x86.x64 -find **/Auxiliary/Build/vcvarsall.bat`) do (
-  call "%%i" x86_amd64
-)
+REM This for loop takes a long time to find vcvarsall.bat,
+REM so I hard-coded the path in. When Github Runner versions change,
+REM the for loop might be needed again to discover the right path.
 
-scons
+REM for /f "usebackq tokens=*" %%i in (`vswhere -latest -products * -requires Microsoft.VisualStudio.Component.VC.Tools.x86.x64 -find **/Auxiliary/Build/vcvarsall.bat`) do (
+REM  @echo "%%i"
+REM  call "%%i" x86_amd64
+REM )
+
+call "C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\VC\Auxiliary\Build\vcvarsall.bat" x86_amd64
+
+scons bits=64