Merge branch 'js-i18n-board-store' into 'master'

i18n boards store directory

See merge request gitlab-org/gitlab-ce!28712

app/assets/javascripts/boards/stores/actions.js

+import { __ } from '~/locale';
+
 const notImplemented = () => {
-  throw new Error('Not implemented!');
+  throw new Error(__('Not implemented!'));
 };
 
 export default {

app/assets/javascripts/boards/stores/mutations.js

 import * as mutationTypes from './mutation_types';
+import { __ } from '~/locale';
 
 const notImplemented = () => {
-  throw new Error('Not implemented!');
+  throw new Error(__('Not implemented!'));
 };
 
 export default {

locale/gitlab.pot

@@ -6473,6 +6473,9 @@ msgstr ""
 msgid "Not found."
 msgstr ""
 
+msgid "Not implemented!"
+msgstr ""
+
 msgid "Not now"
 msgstr ""