update: 升级element

package.json

@@ -16,7 +16,7 @@
     "@tinymce/tinymce-vue": "^1.0.8",
     "axios": "^0.18.0",
     "babel-polyfill": "^6.26.0",
-    "element-ui": "^2.4.0",
+    "element-ui": "^2.15.6",
     "es6-promise": "^4.2.6",
     "less": "^3.0.4",
     "less-loader": "^4.1.0",