Support for product version supplied by AppVeyor (#12)

* Set version of binaries based on CS_VERSION environment variable
* Use AppVeyor supplied product version
* Automatically generate ProductCode GUID
* Convert version (CS_VERSION) to number (CS_VERSION_NUM)

ClassicShellSrc/ClassicShellSetup/__MakeFinal.bat

@@ -1,5 +1,15 @@
 @cd %~dp0
 
+@rem Default version
+@set CS_VERSION=4.4.0
+
+@if defined APPVEYOR_BUILD_VERSION (
+	@set CS_VERSION=%APPVEYOR_BUILD_VERSION%
+)
+
+@rem Convert . to _
+@set CS_VERSION_STR=%CS_VERSION:.=_%
+
 @call BuildBinaries.bat
 @if ERRORLEVEL 1 exit /b 1