Factor out screen settings to ScreenSettings struct

It's a bit annoying to pass each screen setting individually, would be
nice if we could just wrap it up in a nice struct and pass that instead.

desktop_version/src/Screen.cpp

@@ -17,23 +17,27 @@ extern "C"
 	);
 }
 
-void Screen::init(
-	int windowWidth,
-	int windowHeight,
-	bool fullscreen,
-	bool useVsync,
-	int stretch,
-	bool linearFilter,
-	bool badSignal
-) {
+ScreenSettings::ScreenSettings()
+{
+	windowWidth = 320;
+	windowHeight = 240;
+	fullscreen = false;
+	useVsync = false;
+	stretch = 0;
+	linearFilter = false;
+	badSignal = false;
+}
+
+void Screen::init(const ScreenSettings& settings)
+{
 	m_window = NULL;
 	m_renderer = NULL;
 	m_screenTexture = NULL;
 	m_screen = NULL;
-	isWindowed = !fullscreen;
-	stretchMode = stretch;
-	isFiltered = linearFilter;
-	vsync = useVsync;
+	isWindowed = !settings.fullscreen;
+	stretchMode = settings.stretch;
+	isFiltered = settings.linearFilter;
+	vsync = settings.useVsync;
 	filterSubrect.x = 1;
 	filterSubrect.y = 1;
 	filterSubrect.w = 318;
@@ -84,9 +88,9 @@ void Screen::init(
 		240
 	);
 
-	badSignalEffect = badSignal;
+	badSignalEffect = settings.badSignal;
 
-	ResizeScreen(windowWidth, windowHeight);
+	ResizeScreen(settings.windowWidth, settings.windowHeight);
 }
 
 void Screen::LoadIcon()