[Improvement] Support Vue.use to register a component (#401)

packages/col/index.vue

@@ -9,7 +9,9 @@
 </template>
 
 <script>
-export default {
+import { create } from '../utils';
+
+export default create({
   name: 'van-col',
 
   props: {
@@ -26,5 +28,5 @@ export default {
       return this.gutter ? { paddingLeft: padding, paddingRight: padding } : {};
     }
   }
-};
+});
 </script>