Designed navigation style
Inspired a little by https://github.com/JNTian/JTNavigationController
Customize the navigation style to make the transition of UIViewControllers easier. Pull request from anyone is welcomed.
Rewrite a navigation controller not inherited from UINavigationController. This makes our ViewController not using UINavigationBar anymore. Not only the touch area changes, but also the useless push and pop functions in our navigation style disappears.
