feat: 分页组件 (#327)

* feat: 分页组件

* feat: 代码规范化

docs/markdown/en-US/pagination.md

@@ -0,0 +1,104 @@
+
+## Pagination
+
+### Usage
+``` javascript
+import { Pagination } from 'vant';
+
+Vue.component(Pagination.name, Pagination);
+```
+
+### Demo
+
+#### Basic Usage
+
+```html
+<van-pagination 
+  :totalItems="totalItems" 
+  :itemsPerPage="itemsPerPage"
+  :showPageSize="showPageSize2" 
+  previousText= "Prev" 
+  nextText= "Next" 
+  v-model="pagination1" 
+  @change="pageChanged"
+></van-pagination>
+
+<pre>Page: {{pagination1.currentPage}} / {{pagination1.numPages}}</pre>
+```
+
+```javascript
+export default {
+  data() {
+    return  {
+        totalItems: 24,
+        pagination1: {
+            currentPage: 2
+        },
+        pagination2: {
+            currentPage: 1
+        },
+        pagination3: {
+            currentPage: 1
+        },
+        setPage (pageNo) {
+            this.pagination1.currentPage = pageNo;
+        },
+        pageChanged () {
+            console.log('Page changed to: ' + this.pagination1.currentPage);
+        },
+        showPageSize: 3,
+        showPageSize2: 5
+        bigTotalItems: 125,
+        itemsPerPage: 5
+    }
+  }
+}
+```
+
+Set `mode=simple` use Simple Mode
+
+```html
+<van-pagination 
+  :totalItems="bigTotalItems" 
+  v-model="pagination2" 
+  :previousText="'Prev'" 
+  :nextText="'Next'" 
+  mode="simple" 
+></van-pagination>
+<pre>Page: {{pagination2.currentPage}} / {{pagination2.numPages}}</pre>
+```
+
+#### Advanced Usage
+
+Set `forceEllipses: true`, show ellipses
+
+```html
+<van-pagination 
+  :totalItems="bigTotalItems" 
+  v-model="pagination3" 
+  :showPageSize="showPageSize" 
+  :forceEllipses="true"
+  previousText= "Prev" 
+  nextText= "Next" 
+></van-pagination>
+
+<pre>Page: {{pagination3.currentPage}} / {{pagination3.numPages}}</pre>
+```
+
+### API
+
+| Attribute | Description | Type | Default | Accepted Values |
+|-----------|-----------|-----------|-------------|-------------|
+| v-model | pageModel | Object | - | - |
+| mode | mode | String | multi | multi : simple  |
+| itemsPerPage | itemsPerPage | Number | 10 | - |
+| previousText | previousText | String | Previous | - |
+| nextText | nextText | String | Next | - |
+| showPageSize | showPageSize | Number | 5 | - |
+| forceEllipses | ellipses | Boolean | false | - |
+
+### Event
+
+| Event | Description | Attribute |
+|-----------|-----------|-----------|
+| change | triggered on page change | - |