message: [changelog] 1.3.8
diff: ## Changelog
  +### [1.3.8](https://github.com/youzan/vant/tree/v1.3.8)
  +`2018-10-17`
  +
  +**Improvements**
  +
  +- Tag: add size prop [\#1949](https://github.com/youzan/vant/pull/1949)
  +- Tag: add color prop [\#1946](https://github.com/youzan/vant/pull/1946)
  +- Tag: add round prop [\#1947](https://github.com/youzan/vant/pull/1947)
  +- Panel: add icon prop [\#1942](https://github.com/youzan/vant/pull/1942)
  +- Icon: add cart-o icon [\#1932](https://github.com/youzan/vant/pull/1932)
  +- Field: add clear event [\#1944](https://github.com/youzan/vant/pull/1944)
  +- Rate: support touch move select [\#1951](https://github.com/youzan/vant/pull/1951)
  +- AddressList: add switchable prop [\#1938](https://github.com/youzan/vant/pull/1938)
  +
  +**Bug Fixes**
  +
  +- fix Card desc ellipsis [\#1935](https://github.com/youzan/vant/pull/1935)
  +- fix SubmitBar incomplete button text display [\#1940](https://github.com/youzan/vant/pull/1940)
  +
  +
  ### [1.3.7](https://github.com/youzan/vant/tree/v1.3.7)
  `2018-10-12`
  