cut out NavToggle component

browser/components/NavToggleButton.js

@@ -0,0 +1,29 @@
+/**
+* @fileoverview Micro component for toggle SideNav
+*/
+import React, { PropTypes } from 'react'
+import styles from './NavToggleButton.styl'
+import CSSModules from 'browser/lib/CSSModules'
+
+/**
+* @param {boolean} isFolded
+* @param {Function} handleToggleButtonClick
+*/
+
+const NavToggleButton = ({isFolded, handleToggleButtonClick}) => (
+  <button styleName='navToggle'
+    onClick={(e) => handleToggleButtonClick(e)}
+  >
+    {isFolded
+     ? <i className='fa fa-angle-double-right' />
+     : <i className='fa fa-angle-double-left' />
+    }
+  </button>
+)
+
+NavToggleButton.propTypes = {
+  isFolded: PropTypes.bool.isRequired,
+  handleToggleButtonClick: PropTypes.func.isRequired
+}
+
+export default CSSModules(NavToggleButton, styles)