msvcbuild.bat: Update default to 2019, add support for 2022
@echo off
Setlocal EnableDelayedExpansion
-if not defined VS set VS=15
+if not defined VS set VS=16
+if "%APPVEYOR_BUILD_WORKER_IMAGE%"=="Visual Studio 2022" (set VS=17)
if "%APPVEYOR_BUILD_WORKER_IMAGE%"=="Visual Studio 2019" (set VS=16)
if "%APPVEYOR_BUILD_WORKER_IMAGE%"=="Visual Studio 2017" (set VS=15)
if "%APPVEYOR_BUILD_WORKER_IMAGE%"=="Visual Studio 2015" (set VS=14)
