Visit original repo first

This resolves #171, #174, and #178

For now, the original library has problems of using two deprecated modules, ListView and react-native-webview-bridge-updated. ListView problem is solved by Ankit-96 's PR. So I focused on removing react-native-webview-bridge-updated and making use of react-native-webview.

• Did just like what Ankit-96 did; replaced ListView with FlatList
• Replaced react-native-webview-bridge-updated with react-native-webview
  • Instead of injecting MessageHandler into webpage(WebViewBridge) and sending message through sendToBridge, I directly inject zss_editor's function calls through injectJavaScript. To achieve that, I fixed WebViewMessageHandler.js to be mapper function, translating functions of RichTextEditor to those of zss_editor.
  • In editor.html, replace WebViewBridge.send with ReactNativeWebView.postMessage
• Added ./newExample. You should $ cd newExample; yarn; cd ios; pod install; cd ..; react-native run-ios;.

• $ yarn add https://github.com/jb-/react-native-zss-rich-text-editor
• $ yarn add react-native-webview (I'm not sure why I have to do this)
• $ cd ios; pod install;

• Tested on RN 0.61.5, iOS only.

• Since I worked it for my project only, I did not test it on other versions or on Android platform. If any of you are familiar with both Android and iOS natives, please refer to my project and collaborate.

• https://github.com/react-native-community/react-native-webview/blob/master/docs/Guide.md#communicating-between-js-and-native