fixed bug for `Tab.remove`

1. `lib`新增`indexOf`用于数组的单项查询
2. 调整了`Tab.remove`内的循环方式，解决`Tab.add`重复页卡后能正确批量删除。
3. 更新了`Tab`控件的相关测试用例和DEMO
optimize the code to improve performance

optimize the code to improve performance
Merge pull request #150 from zfkun/3.0.2

fixed bug for `Tab.remove`