Exit script on msbuild error

Author: code-disaster

build-natives/build-win.bat

@@ -2,10 +2,12 @@
 
 premake5 --file=build-win.lua %1
 msbuild steamworks4j.sln /p:Configuration=ReleaseDLL /p:Platform=Win32 /t:Rebuild
+@if %ERRORLEVEL% neq 0 exit /b %ERRORLEVEL%
 copy bin\x32\ReleaseDLL\steamworks4j.dll ..\java-wrapper\src\main\resources\steamworks4j.dll
 copy bin\x32\ReleaseDLL\steamworks4j-server.dll ..\server\src\main\resources\steamworks4j-server.dll
 copy bin\x32\ReleaseDLL\steamworks4j-encryptedappticket.dll ..\server\src\main\resources\steamworks4j-encryptedappticket.dll
 msbuild steamworks4j.sln /p:Configuration=ReleaseDLL /p:Platform=x64 /t:Rebuild
+@if %ERRORLEVEL% neq 0 exit /b %ERRORLEVEL%
 copy bin\x64\ReleaseDLL\steamworks4j.dll ..\java-wrapper\src\main\resources\steamworks4j64.dll
 copy bin\x64\ReleaseDLL\steamworks4j-server.dll ..\server\src\main\resources\steamworks4j-server64.dll
 copy bin\x64\ReleaseDLL\steamworks4j-encryptedappticket.dll ..\server\src\main\resources\steamworks4j-encryptedappticket64.dll