make it possible to disable application of `Form-offset` style on FormLabel component.

resources/frontend_client/app/components/form/FormLabel.react.js

 "use strict";
 
 import React, { Component, PropTypes } from "react";
+import cx from "classnames";
 
 
 export default class FormLabel extends Component {
 
     render() {
-        let { fieldName, formError, message, title } = this.props;
+        let { fieldName, formError, message, offset, title } = this.props;
 
         if (!message) {
             message = (formError && formError.data.errors && fieldName in formError.data.errors) ? formError.data.errors[fieldName] : undefined;
         }
 
         return (
-            <label className="Form-label Form-offset">{title}: { message !== undefined ? <span>{message}</span> : null }</label>
+            <label className={cx("Form-label", {"Form-offset": offset})}>{title}: { message !== undefined ? <span>{message}</span> : null }</label>
         );
     }
 }
@@ -22,5 +23,5 @@ FormLabel.propTypes = {
     fieldName: PropTypes.string.isRequired,
     formError: PropTypes.object,
     message: PropTypes.string,
-    title: PropTypes.string.isRequired
+    offset: true,
 }