extra debugging thing for visual studio

I think this prevents random "exited with code 3" errors, but I can't remember ...

src/PowderToySDL.cpp

@@ -953,6 +953,9 @@ void SigHandler(int signal)
 
 int main(int argc, char * argv[])
 {
+#if defined(_DEBUG) && defined(_MSC_VER)
+	_CrtSetReportMode(_CRT_ASSERT, _CRTDBG_MODE_DEBUG);
+#endif
 	currentWidth = WINDOWW; 
 	currentHeight = WINDOWH;