Docs: add English language support (#170)

* feat: support lang entry build

* feat: vant support lang switch

* move lang iframe-router to utils & fix router link bug

* add en-US config && add some translation

* chang async. to async_ (support superman cdn)

* add layout translation

* change nav style

* upgrade zan-doc

* fix: doc config

* upgrade zan-doc && remove useless code

* fix changelog generate path

docs/src/components/demo-list.vue

@@ -3,7 +3,7 @@
     <h1 class="zanui-title">Zan UI</h1>
     <h2 class="zanui-desc">有赞移动端 Vue 组件库</h2>
     <div class="mobile-navs">
-      <div class="mobile-nav-item" v-for="(item, index) in data" v-if="item.showInMobile" :key="index">
+      <div class="mobile-nav-item" v-for="(item, index) in navList" v-if="item.showInMobile" :key="index">
         <mobile-nav v-for="(group, index) in item.groups" :group="group" :base="base" :nav-key="index" :key="index" />
       </div>
     </div>
@@ -13,17 +13,36 @@
 <script>
 import docConfig from '../doc.config';
 import MobileNav from './mobile-nav';
+import { getLang } from '../utils/lang';
 
 export default {
   data() {
     return {
-      data: docConfig['zh-CN'].nav,
-      base: '/component'
+      docConfig,
+      lang: getLang()
     };
   },
 
+  beforeRouteEnter(to, from, next) {
+    next(vm => vm.lang = to.meta.lang);
+  },
+
+  beforeRouteUpdate(to, from, next) {
+    this.lang = to.meta.lang;
+  },
+
   components: {
     MobileNav
+  },
+
+  computed: {
+    base() {
+      return `${this.lang}/component`;
+    },
+
+    navList() {
+      return this.docConfig[this.lang].nav || [];
+    }
   }
 };
 </script>

docs/src/components/mobile-nav.vue

@@ -17,7 +17,7 @@
             v-if="!navItem.disabled">
             <router-link
               active-class="active"
-              :to="base + navItem.path">
+              :to="'/' + base + navItem.path">
               <p>
                 {{ navItem.title }}
               </p>