Add animation for Tooltip

components/popover/index.jsx

@@ -4,14 +4,14 @@ var React = require('react');
 var Tooltip = require('rc-tooltip');
 
 module.exports = React.createClass({
-  getDefaultProps: function () {
+  getDefaultProps() {
     return {
       transitionName: '',
       placement: 'top',
       trigger: 'hover'
     };
   },
-  render: function() {
+  render() {
     var overlay = <div>
       <div className="popover-title">
         {this.props.title}

components/tooltip/index.jsx

@@ -4,16 +4,23 @@ var React = require('react');
 var Tooltip = require('rc-tooltip');
 
 module.exports = React.createClass({
-  getDefaultProps: function () {
+  getDefaultProps() {
     return {
       placement: 'top'
     };
   },
-  render: function() {
+  render() {
+    var transitionName = ({
+      top: 'zoom-down',
+      bottom: 'zoom-up',
+      left: 'zoom-right',
+      right: 'zoom-left'
+    })[this.props.placement];
     return (
       <Tooltip placement={this.props.placement}
         prefixCls="ant-tooltip"
         trigger={this.props.trigger}
+        transitionName={transitionName}
         overlay={this.props.title}>
         {this.props.children}
       </Tooltip>