Implement Start+Select+L1+R1 shortcut to quit

Fixes #548

Limelight/ViewControllers/StreamFrameViewController.m

@@ -104,7 +104,7 @@
     [_spinner startAnimating];
     _spinner.center = CGPointMake(self.view.frame.size.width / 2, self.view.frame.size.height / 2 - _stageLabel.frame.size.height - _spinner.frame.size.height);
     
-    _controllerSupport = [[ControllerSupport alloc] initWithConfig:self.streamConfig presenceDelegate:self];
+    _controllerSupport = [[ControllerSupport alloc] initWithConfig:self.streamConfig delegate:self];
     _inactivityTimer = nil;
     
     _streamView = [[StreamView alloc] initWithFrame:self.view.frame];
@@ -615,6 +615,12 @@
 #endif
 }
 
+- (void) streamExitRequested {
+    Log(LOG_I, @"Gamepad combo requested stream exit");
+    
+    [self returnToMainFrame];
+}
+
 - (void)userInteractionBegan {
     // Disable hiding home bar when user is interacting.
     // iOS will force it to be shown anyway, but it will