message: [changelog] 1.6.10
diff: ## Changelog
  +## [v1.6.10](https://github.com/youzan/vant/tree/v1.6.10)
  +`2019-03-17`
  +
  +**Improvements**
  +
  +- Icon: add tag prop [\#2986](https://github.com/youzan/vant/pull/2986)
  +- Cell: add label slot [\#2956](https://github.com/youzan/vant/pull/2956)
  +- Toast: add onClose prop [\#2964](https://github.com/youzan/vant/pull/2964)
  +- AddressEdit: add setAddressDetail method [\#2984](https://github.com/youzan/vant/pull/2984)
  +
  +**Bug Fixes**
  +
  +- fix List render error by adding a loading key [\#2983](https://github.com/youzan/vant/pull/2983)
  +- fix Steps incorrect active style in vertical direction [\#2981](https://github.com/youzan/vant/pull/2981)
  +- fix Coupon value-desc display condition [\#2980](https://github.com/youzan/vant/pull/2980)
  +- fix Uploader can not upload same file when before-read [\#2971](https://github.com/youzan/vant/pull/2971)
  +
  +
  ## [v1.6.9](https://github.com/youzan/vant/tree/v1.6.9)
  `2019-03-11`
  