message: docs(changelog): 2.1.4
diff: # Changelog
  +### [v2.1.4](https://github.com/youzan/vant/tree/v2.1.4)
  +`2019-08-21`
  +
  +**Improvements**
  +
  +- Col: add click event [\#4169](https://github.com/youzan/vant/pull/4169)
  +- Row: add click event [\#4170](https://github.com/youzan/vant/pull/4170)
  +- Area: add is-oversea-code prop [\#4163](https://github.com/youzan/vant/pull/4163)
  +- Circle: support gradient color [\#4157](https://github.com/youzan/vant/pull/4157)
  +- Circle: support number type of size prop [\#4160](https://github.com/youzan/vant/pull/4160)
  +- Tabbar: support match route by to.name [\#4148](https://github.com/youzan/vant/pull/4148)
  +- Sku: should close image preview when popstate [\#4152](https://github.com/youzan/vant/pull/4152)
  +- Uploader: should close image preview when popstate [\#4151](https://github.com/youzan/vant/pull/4151)
  +- Uploader: support more image types [\#4140](https://github.com/youzan/vant/pull/4140)
  +- TreeSelect: support multiple select [\#4130](https://github.com/youzan/vant/pull/4130)
  +- TreeSelect: active-id support sync modifier [\#4133](https://github.com/youzan/vant/pull/4133)
  +- TreeSelect: main-active-index support sync modifier [\#4132](https://github.com/youzan/vant/pull/4132)
  +
  +**Bug Fixes**
  +
  +- fix Sku unextracted i18n message [\#4172](https://github.com/youzan/vant/pull/4172)
  +- fix Tabbar avoid navigation duplicated [\#4147](https://github.com/youzan/vant/pull/4147)
  +- fix Field button width shrinked in firefox [\#4144](https://github.com/youzan/vant/pull/4144)
  +- fix Picker prevent style be override by base.css [\#4136](https://github.com/youzan/vant/pull/4136)
  +
  +
  ### [v2.1.3](https://github.com/youzan/vant/tree/v2.1.3)
  `2019-08-15`
  