iOS: Refactoring

Enabled ARC for iOS.
Weakify/Strongify macros for objc blocks.
Removed old version checks.
Specific types for ObjC++ modules to exclude unneeded bridging.
Separate DeviceMetrics class for device specific data.
Replaced old/deprecated functionality.

modules/camera/camera_ios.mm

@@ -124,18 +124,12 @@
 	if (output) {
 		[self removeOutput:output];
 		[output setSampleBufferDelegate:nil queue:NULL];
-		[output release];
 		output = nil;
 	}
 
 	[self commitConfiguration];
 }
 
-- (void)dealloc {
-	// bye bye
-	[super dealloc];
-}
-
 - (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection *)connection {
 	// This gets called every time our camera has a new image for us to process.
 	// May need to investigate in a way to throttle this if we get more images then we're rendering frames..
@@ -272,7 +266,6 @@ CameraFeedIOS::CameraFeedIOS() {
 
 void CameraFeedIOS::set_device(AVCaptureDevice *p_device) {
 	device = p_device;
-	[device retain];
 
 	// get some info
 	NSString *device_name = p_device.localizedName;
@@ -286,14 +279,12 @@ void CameraFeedIOS::set_device(AVCaptureDevice *p_device) {
 };
 
 CameraFeedIOS::~CameraFeedIOS() {
-	if (capture_session != NULL) {
-		[capture_session release];
-		capture_session = NULL;
+	if (capture_session) {
+		capture_session = nil;
 	};
 
-	if (device != NULL) {
-		[device release];
-		device = NULL;
+	if (device) {
+		device = nil;
 	};
 };
 
@@ -312,8 +303,7 @@ void CameraFeedIOS::deactivate_feed() {
 	// end camera capture if we have one
 	if (capture_session) {
 		[capture_session cleanup];
-		[capture_session release];
-		capture_session = NULL;
+		capture_session = nil;
 	};
 };
 
@@ -347,8 +337,6 @@ void CameraFeedIOS::deactivate_feed() {
 	// remove notifications
 	[[NSNotificationCenter defaultCenter] removeObserver:self name:AVCaptureDeviceWasConnectedNotification object:nil];
 	[[NSNotificationCenter defaultCenter] removeObserver:self name:AVCaptureDeviceWasDisconnectedNotification object:nil];
-
-	[super dealloc];
 }
 
 @end
@@ -453,5 +441,5 @@ CameraIOS::CameraIOS() {
 };
 
 CameraIOS::~CameraIOS() {
-	[device_notifications release];
+	device_notifications = nil;
 };