Image button in tinyMCE now displays an icon instead of text

tracim/tracim/templates/pod.mak

               //////////////////////////////////////////////
               // add custom btn to handle image by selecting them with system explorer
               $editor.addButton('customInsertImage', {
-                text: 'Image',
-                icon: false,
+                icon: 'mce-ico mce-i-image',
                 onclick: function () {
                   if ($('#hidden_tinymce_fileinput').length > 0) $('#hidden_tinymce_fileinput').remove()