chore(edit) showMessage: add comment

lib/client/edit.js

@@ -490,6 +490,13 @@ var CloudCmd, Util, DOM, CloudFunc, ace, DiffProto, diff_match_patch, Zip, MenuI
                 });
             }
             
+            /* 
+             * Msg should be created and removed
+             * if it's not and just inner text
+             * is changing, and hide and show of DOM
+             * is called - bug occures: empty box
+             * with no text inside.
+             */
             Msg = DOM.load({
                 name        : 'div',
                 className   : 'msg',