Added tvOS paltform support (#682)

* [tvOS] Update podspec

* [tvOS] Add tvOS target

* Update README.md

* [docs] Folder that contains pictures and content for documentation

* tvOS Readme

* [JPEG] Update image to JPEG

react-native-video.podspec

@@ -11,7 +11,9 @@ Pod::Spec.new do |s|
   s.homepage     = "https://github.com/brentvatne/react-native-video"
 
   s.license      = "MIT"
-  s.platform     = :ios, "7.0"
+
+  s.ios.deployment_target = "7.0"
+  s.tvos.deployment_target = "9.0"
 
   s.source       = { :git => "https://github.com/brentvatne/react-native-video.git", :tag => "#{s.version}" }