update radio demos

components/radio/demo/disable.md

@@ -29,7 +29,7 @@ var App = React.createClass({
       <Radio defaultChecked={false} disabled={this.state.disabled} />不可用
       <br />
       <Radio defaultChecked={true} disabled={this.state.disabled} />不可用
-      <div style={{"margin-top": 20}}>
+      <div style={{marginTop: 20}}>
         <button className="ant-btn ant-btn-primary" onClick={this.toggleDisabled}>
           Toggle disabled
         </button>

components/radio/demo/group.md

@@ -50,7 +50,7 @@ var RadioGroup = React.createClass({
             选项D
         </label>
       </p>
-      <p style={{"margin-top": 20}}>
+      <p style={{marginTop: 20}}>
         你选中了：{this.state.value} 。
       </p>
     </div>;