Fix "Unsupported rule: jsDoc" when linting

no issue
- add missing jscs-jsdoc dependency and specify plugin in .jscsrc
- fix linting issue in user-test.js

.jscsrc

@@ -1,4 +1,7 @@
 {
+    "plugins": [
+        "jscs-jsdoc"
+    ],
     "additionalRules": [ "core/test/utils/jscs-rules/*.js" ],
     "requireCurlyBraces": [
         "if",

core/client/tests/unit/models/user-test.js

@@ -4,7 +4,7 @@ import {
     it
 } from 'ember-mocha';
 
-const { run } = Ember;
+const {run} = Ember;
 
 describeModel(
     'user',

package.json

@@ -87,6 +87,7 @@
     "grunt-mocha-istanbul": "2.4.0",
     "grunt-shell": "1.1.2",
     "grunt-update-submodules": "0.4.1",
+    "jscs-jsdoc": "1.2.0",
     "matchdep": "0.3.0",
     "nock": "2.3.0",
     "rewire": "2.3.3",