Revert "don't allow to click on links"

It doesn't conver all the cases. There's a better and simpler fix.

This reverts commit 8b07524110.

src/RichTextEditor.js

           injectedJavaScript={injectScript}
           source={pageSource}
           onLoad={() => this.init()}
-          onShouldStartLoadWithRequest={(event) => {return this._onShouldStartLoadWithRequest(event)}}
         />
         {this._renderLinkModal()}
       </View>
     );
   }
 
-  _onShouldStartLoadWithRequest(event) {
-    return (event.url.indexOf('editor.html') != -1);
-  }
-
   escapeJSONString = function(string) {
     return string
       .replace(/[\\]/g, '\\\\')