Add comment about unprocessed code in JS files

amd/src/filter.js

@@ -6,7 +6,9 @@
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 
+/* This comment is just there to keep grunt satisfied and won't be processed at runtime */
 /* global define, M */
+
 define(['jquery'], function ($) {
     "use strict";
 

amd/src/hidecourse.js

@@ -6,7 +6,9 @@
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 
+/* This comment is just there to keep grunt satisfied and won't be processed at runtime */
 /* global define, M */
+
 define(['jquery'], function ($) {
     "use strict";
 

amd/src/hidenews.js

@@ -6,7 +6,9 @@
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 
+/* This comment is just there to keep grunt satisfied and won't be processed at runtime */
 /* global define, M */
+
 define(['jquery'], function ($) {
     "use strict";