[new feature] ImagePreview support manually close (#346)

* fix: Tabbar icon line-height

* [new feature] progress add showPivot prop

* [new feature] TabItem support vue-router

* [new feature] update document header style

* [Doc] add toast english ducoment

* [bugfix] Search box-sizing wrong

* [Doc] update vant-demo respo

* [Doc] translate theme & demo pages

* [Doc] add Internationalization document

* [bugfix] remove unnecessary props

* [fix] optimize clickoutside

* [new feature] optimize find-parent

* [new feature]: change document title accordinng to language

* [new feature] Pagination code review

* [improvement] adjust icon-font unicode

* [improvement] Icon spinner color inherit

* [improvement] icon default width

* [bugfix] DateTimePicker validate date props

* [bugfix] Tab item text ellipsis

* [improvement] optimize single line ellipsis

* [Improvement] optimzie staticClass

* [Improvement] Button: use sfc instread of jsx

* [Improvement] update actionsheet close icon style

* fix: yarn.lock

* fix: icon test cases

* [bugfix] errors during ssr

* [Improvement] SubmitBar add left slot

* [new feature] ImagePreview support manually close

* fix: ImagePreview test case

test/unit/specs/image-preview.spec.js

@@ -34,6 +34,9 @@ describe('ImagePreview', () => {
     wrapper = mount(ImagePreviewVue);
     wrapper.vm.images = images;
     wrapper.vm.value = true;
+    wrapper.vm.$on('input', val => {
+      wrapper.vm.value = val;
+    });
 
     expect(wrapper.hasClass('van-image-preview')).to.be.true;