仿造 微信webView效果，包括：
an iOS native ViewController like WeChat webview Controller, which includes:
1进度条，
1 progress bar
2左滑返回上个网页或者直接关闭(像UINavigationController)，
2 back button to go back in webview OR pop back in navigation stack
3适配iOS8.0的UIWebView(特别处理UIWebView内存泄漏)和WKWebView，
3 adapt to iOS 8.0 for UIWebView(especially for memory leaks of UIWebView) and WKWebView
4支持JS和OC交互HybridApp，
4 send messages between JS and OC, that's part of Hybrid App.
5支持WebViewProxy
5 support WebViewProxy
支持JS和OC交互，说明：http://hawkingouyang.com/2016/08/10/6_ObjC-JS-and-Native-WebView/
Here is a demo gif:
