Update README.md

Author: vip-git

README.md

@@ -49,6 +49,7 @@ import MaterialJsonSchemaForm from 'react-jsonschema-form-material-ui';
 // Internals
 const givenSchema = require('./path-to your-schema.json');
 const givenUISchema = require('./path-to your-ui-schema.json');
+const givenXhrSchema = require('./path-to your-xhr-schema.json');
 const givenFormData = require('./path-to your-ui-formData.json');
 
 const Example () => {