show headset view in monitor window

src/bin/vrtue.rs

@@ -14,7 +14,7 @@ pub fn main() {
   let mut vr = vr::VR::new().expect("VR init");
 
   let mut window: PistonWindow =
-    WindowSettings::new("Hello Virtual World!", [512; 2])
+    WindowSettings::new("Hello, Britannia!", [1024; 2])
         .exit_on_esc(true)
         .vsync(false)
         .build().expect("Building Window");