Resolve "Sort updated comments chronoligically"

Closes #167 (closed)

frontend/src/components/submission_notes/base/FeedbackComment.vue

@@ -98,7 +98,7 @@ export default {
       type: String,
       required: true
     },
-    created: {
+    modified: {
       type: String,
       required: false
     },
@@ -133,8 +133,8 @@ export default {
     },
     markedForDeletion () { return SubmissionNotes.state.commentsMarkedForDeletion },
     parsedCreated () {
-      if (this.created) {
-        return new Date(this.created).toLocaleString()
+      if (this.modified) {
+        return new Date(this.modified).toLocaleString()
       } else {
         return 'Just now'
       }