message: Update index.html for website
diff: -<!DOCTYPE html>
  +<!doctype html>
  <head>
  - <meta charset="utf-8" />
  + <meta charset="utf-8">
  <title>react-docgen Playground</title>
  - <meta
  - name="viewport"
  - content="initial-scale=1.0,user-scalable=no,maximum-scale=1,width=device-width"
  - />
  - <meta name="keywords" content="react,reactjs,react-docgen,playground" />
  - <meta
  - name="description"
  - content="A CLI and toolbox to extract information from React component files for documentation generation purposes."
  - />
  - <meta property="og:locale" content="en-us" />
  - <meta property="og:title" content="react-docgen" />
  - <meta
  - property="og:description"
  - content="A CLI and toolbox to extract information from React component files for documentation generation purposes."
  - />
  - <meta property="og:url" content="http://reactcommunity.org/react-docgen" />
  - <meta property="og:site_name" content="react-docgen" />
  - <meta property="og:type" content="article" />
  + <meta name="keywords" content="react,reactjs,react-docgen,playground,flow,javascript">
  + <meta name="description" content="A CLI and toolbox to extract information from React component files for documentation generation purposes.">
  + <meta property="og:locale" content="en-us">
  + <meta property="og:title" content="react-docgen">
  + <meta property="og:description" content="A CLI and toolbox to extract information from React component files for documentation generation purposes.">
  + <meta property="og:url" content="https://reactcommunity.org/react-docgen/">
  + <meta property="og:site_name" content="react-docgen">
  + <meta property="og:type" content="article">
  </head>
  <body>
  <header class="page-header">
  