Fix null item in kanban

www/kanban/inner.js

@@ -286,7 +286,7 @@ define([
                 kanban.inEditMode = true;
                 // create a form to enter element
                 var boardId = $(el.parentNode.parentNode).attr("data-id");
-                var $item = $('<div>', {'class': 'kanban-item'});
+                var $item = $('<div>', {'class': 'kanban-item new-item'});
                 var $input = getInput().val(name).appendTo($item);
                 kanban.addForm(boardId, $item[0]);
                 $input.focus();

www/kanban/jkanban.js

@@ -147,9 +147,13 @@
                         self.drake = self.dragula(self.boardContainer, {
                             moves: function (el, source, handle, sibling) {
                                 if (self.options.readOnly) { return false; }
+                                if (el.classList.contains('new-item')) { return false; }
                                 return handle.classList.contains('kanban-item');
                             },
                             accepts: function (el, target, source, sibling) {
+                                if (sibling === null) {
+                                    return false;
+                                }
                                 if (self.options.readOnly) { return false; }
                                 return true;
                             },