docs: update documentation examples to work with react-docgen@5

Author: ZauberNerd

README.md

@@ -1,7 +1,9 @@
-# react-docgen-displayname-handler [![Build Status](https://travis-ci.org/nerdlabs/react-docgen-displayname-handler.svg?branch=master)](https://travis-ci.org/nerdlabs/react-docgen-displayname-handler)
+# react-docgen-displayname-handler ![Build Status](https://img.shields.io/travis/nerdlabs/react-docgen-displayname-handler/master) ![Latest published version](https://img.shields.io/npm/v/react-docgen-displayname-handler)
+
 A handler for react-docgen that tries to infer the displayName of a component.
 
 ## Rationale
+
 [react-docgen](https://github.com/reactjs/react-docgen) is a CLI and API toolbox
 to help extract information from [React](http://facebook.github.io/react/)
 components and generate documentation from it.
@@ -10,6 +12,7 @@ components and generate documentation from it.
 used to infer the displayName for a given component.
 
 The handler tries to infer the displayName from the following sources:
+
 - a static `displayName` property on the object / class
 - the name of the function or class declaration/expression
 - the name of the variable the component is assigned to
@@ -18,13 +21,15 @@ The handler tries to infer the displayName from the following sources:
 - if everything fails the displayName is set to `UnknownComponent`
 
 ## Installation
+
 Install `react-docgen-displayname-handler` from [npm](https://www.npmjs.com/package/react-docgen-displayname-handler)
 
 ```shell
 npm install --save react-docgen-displayname-handler
 ```
 
 ## Usage
+
 Unfortunately there is currently no easy way to use custom handlers with the
 [react-docgen CLI](https://github.com/reactjs/react-docgen#cli).
 
@@ -43,27 +48,31 @@ const resolver = reactDocs.resolver.findExportedComponentDefinition;
 const handlers = reactDocs.handlers.concat(displayNameHandler);
 const documentation = reactDocs.parse(src, resolver, handlers);
 ```
+
 If you want to use the filepath for displayName resolution too, check out the
 following example:
+
 ```javascript
 import reactDocs from 'react-docgen';
 import { createDisplayNameHandler } from 'react-docgen-displayname-handler';
 const resolver = reactDocs.resolver.findExportedComponentDefinition;
 const handlers = reactDocs.handlers.concat(createDisplayNameHandler(filePath));
 const documentation = reactDocs.parse(src, resolver, handlers);
 ```
+
 In order to use the file path too, you need to import the named export
 `createDisplayNameHandler` which takes as an argument the file path and returns
 a handler function that can be passed to react-docgen.
 
 ## Examples
+
 When using this custom handler with `react-docgen` it will try to find the
 displayName of the component as outlined above.
 
 ```javascript
 import React from 'react';
-export default class X {
-  static displayName = 'MyComponent'
+export default class X extends React.Component {
+  static displayName = 'MyComponent';
   render() {
     return <div />;
   }
@@ -79,7 +88,7 @@ export default class X {
 
 ```javascript
 import React from 'react';
-export default class MyComponent {
+export default class MyComponent extends React.Component {
   render() {
     return <div />;
   }