fix(comment) comments via email notification

Github sends emails to users who are subscribed to
notifications. The Gitalk comment behavior should match that of
Github.

The previous behavior does not hide extended email replys.
Often times the email response contains the complete email
chain. The visible email chain confuses the user with
unformatted html strings.

Incorrect comment formatting for email replies. #224

src/component/comment.jsx

@@ -1,4 +1,5 @@
 import React, { Component } from 'react'
+import ReactDOM from 'react-dom'
 import Avatar from './avatar'
 import Svg from './svg'
 import distanceInWordsToNow from 'date-fns/distance_in_words_to_now'
@@ -28,6 +29,22 @@ if (typeof window !== `undefined`) {
 
 
 export default class Comment extends Component {
+  shouldComponentUpdate () {
+    return false
+  }
+
+  componentDidMount () {
+    const comment = ReactDOM.findDOMNode(this)
+    const emailResponse = comment.querySelector('.email-hidden-toggle>a')
+    if (emailResponse) {
+      emailResponse.setAttribute('href', '')
+      emailResponse.addEventListener('click', e => {
+        e.preventDefault()
+        comment.querySelector('.email-hidden-reply').classList.toggle('expanded')
+      }, true)
+    }
+  }
+
   render () {
     const {
       comment,

src/style/index.styl

@@ -412,6 +412,11 @@ $gt-size-avatar-mobi := em(32px)
       right: 0
     &-body
       color: $gt-color-comment-txt !important
+      .email-hidden-reply
+        display: none;
+        white-space: pre-wrap
+      .email-hidden-reply.expanded
+        display: block
     &-admin
       .gt-comment-content
         background-color: $gt-color-comment-adminbg