feat: add plugins management (#3909)

ios/Video/RNVPlugin.swift

@@ -0,0 +1,23 @@
+//
+//  RNVPlugin.swift
+//  react-native-video
+//
+
+import Foundation
+
+public protocol RNVPlugin {
+    /**
+     * Function called when a new player is created
+     * @param id: a random string identifying the player
+     * @param player: the instantiated player reference
+     */
+    func onInstanceCreated(id: String, player: Any)
+    /**
+     * Function called when a player should be destroyed
+     * when this callback is called, the plugin shall free all
+     * resources and release all reference to Player object
+     * @param id: a random string identifying the player
+     * @param player: the player to release
+     */
+    func onInstanceRemoved(id: String, player: Any)
+}