fixed the async action so it doesn't generate extra webpack files

Author: matt-sanders

src/components/index.js

@@ -1,12 +1,14 @@
 import FormlyForm from './FormlyForm.vue';
+import FormlyField from './FormlyField.vue';
 
 export default function(Vue){
     Vue.component('formly-form', FormlyForm);
+    
     Vue.component('formly-field', (resolve) => {
         /**
          * FormlyField must be loaded asyncronously so that any fields added in 
          * via Formly.addType are available
          */
-        require(['./FormlyField.vue'], resolve);
+        resolve(FormlyField);
     });
 }