[new feature] add i18n support (#310)

* 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

* [new feature] add i18n support

* feat: Extract demos from markdown

* feat: Base components demos

* [new feature] complete demo extract & translate

* [fix] text cases

* fix: add deepAssign test cases

* fix: changelog detail

* [new feature] AddressEdit support i18n

docs/demos/views/address-edit.vue

@@ -0,0 +1,69 @@
+<template>
+  <demo-section>
+    <demo-block :title="$t('basicUsage')">
+      <van-address-edit
+        :areaList="areaList"
+        :showPostal="true"
+        :showSetDefault="true"
+        :showSearchResult="true"
+        :searchResult="searchResult"
+        @save="onSave"
+        @delete="onDelete"
+        @change-detail="onChangeDetail"
+      />
+    </demo-block>
+  </demo-section>
+</template>
+
+<script>
+import areaList from '../mock/area.json';
+
+export default {
+  i18n: {
+    'zh-CN': {
+
+    },
+    'en-US': {
+
+    }
+  },
+
+  data() {
+    return {
+      areaList,
+      searchResult: []
+    };
+  },
+
+  methods: {
+    onSave() {
+      Toast('save');
+    },
+
+    onDelete() {
+      Toast('delete');
+    },
+
+    onChangeDetail(val) {
+      if (val) {
+        this.searchResult = [{
+          name: '黄龙万科中心',
+          address: '杭州市西湖区'
+        }, {
+          name: '黄龙万科中心H座'
+        }, {
+          name: '黄龙万科中心H座',
+          address: '杭州市西湖区'
+        }];
+      } else {
+        this.searchResult = [];
+      }
+    }
+  }
+};
+</script>
+
+
+<style lang="postcss">
+
+</style>