add no-var rule to eslint

.eslintrc.js

@@ -69,6 +69,7 @@ module.exports = {
       "error",
       { "args": "none" }
     ],
+    "no-var": [ "error" ],
     "quotes": [
       "error",
       "single"

lib/routes/comment.js

@@ -1,9 +1,8 @@
 module.exports = function(crowi, app) {
   'use strict';
 
-  var debug = require('debug')('growi:routs:comment')
+  const debug = require('debug')('growi:routs:comment')
     , Comment = crowi.model('Comment')
-    , User = crowi.model('User')
     , Page = crowi.model('Page')
     , ApiResponse = require('../util/apiResponse')
     , actions = {}
@@ -20,8 +19,8 @@ module.exports = function(crowi, app) {
    * @apiParam {String} revision_id Revision Id.
    */
   api.get = function(req, res) {
-    var pageId = req.query.page_id;
-    var revisionId = req.query.revision_id;
+    const pageId = req.query.page_id;
+    const revisionId = req.query.revision_id;
 
     if (revisionId) {
       return Comment.getCommentsByRevisionId(revisionId)
@@ -81,7 +80,7 @@ module.exports = function(crowi, app) {
    * @apiParam {String} comment_id Comment Id.
    */
   api.remove = function(req, res) {
-    var commentId = req.body.comment_id;
+    const commentId = req.body.comment_id;
     if (!commentId) {
       return Promise.resolve(res.json(ApiResponse.error('\'comment_id\' is undefined')));
     }