iOS Swift Conversion (#2527)

Converts iOS implementation from Objective-c to Swift

# During the conversion process some updates to the code structure were also made
- Modularize codebase from single file to smaller focused files
- Untangled large nested IF statements
- Added more null checks, since Swift is more strict with null pointers
- Added property to allow for decoding of local video sources with self contained key for offline playback
- Updates example apps to test react-native 0.63.4 and uses auto native dependency imports for android and ios

ios/Video/RCTVideoPlayerViewController.swift

@@ -0,0 +1,44 @@
+import AVKit
+
+class RCTVideoPlayerViewController: AVPlayerViewController {
+    
+    var rctDelegate:RCTVideoPlayerViewControllerDelegate!
+    
+    // Optional paramters
+    var preferredOrientation:String?
+    var autorotate:Bool?
+    
+    func shouldAutorotate() -> Bool {
+
+        if autorotate! || preferredOrientation == nil || (preferredOrientation!.lowercased() == "all") {
+            return true
+        }
+
+        return false
+    }
+
+    override func viewDidDisappear(_ animated: Bool) {
+        super.viewDidDisappear(animated)
+        rctDelegate.videoPlayerViewControllerWillDismiss(playerViewController: self)
+        rctDelegate.videoPlayerViewControllerDidDismiss(playerViewController: self)
+    }
+
+    #if !TARGET_OS_TV
+
+    func supportedInterfaceOrientations() -> UIInterfaceOrientationMask {
+        return .all
+    }
+
+    func preferredInterfaceOrientationForPresentation() -> UIInterfaceOrientation {
+        if preferredOrientation?.lowercased() == "landscape" {
+            return .landscapeRight
+        } else if preferredOrientation?.lowercased() == "portrait" {
+            return .portrait
+        } else {
+            // default case
+            let orientation = UIApplication.shared.statusBarOrientation
+            return orientation
+        }
+    }
+    #endif
+}