Windows build environment:

- Added build script
- Added build-installer script
- Added pack script
- Added gitlog script
- Use shadow build

build_scripts/Windows/tools/get-qt-version.bat

@@ -0,0 +1,34 @@
+:: Usage:
+:: call get-qt-version.bat variable
+
+setlocal
+
+set Var=%~1
+if "%Var%"=="" (
+	echo.
+	echo Parameter error.
+	exit /B 1
+)
+
+set QtVersion=
+
+call "%~dp0find-in-path.bat" QMakePath qmake.exe
+if "%QMakePath%"=="" (
+	echo.
+	echo Cannot find qmake.exe in PATH.
+	goto exit
+)
+
+qmake.exe -version >"%~dp0qtversion.tmp"
+for /F "tokens=1,2,3,4" %%A in (%~sdp0qtversion.tmp) do (
+	if "%%A"=="Using" (
+		set QtVersion=%%D
+		goto exit
+	)
+)
+
+:exit
+if exist "%~dp0qtversion.tmp" del /Q "%~dp0qtversion.tmp"
+
+endlocal & set %Var%=%QtVersion%
+exit /B 0