feat: 分页组件 (#327)

* feat: 分页组件

* feat: 代码规范化

docs/demos/views/pagination.vue

@@ -0,0 +1,94 @@
+<template>
+  <demo-section>
+    <demo-block :title="$t('basicUsage')">
+      <van-pagination 
+        :totalItems="totalItems" 
+        :itemsPerPage="itemsPerPage"
+        :showPageSize="showPageSize2" 
+        :previousText= "$t('prevText')" 
+        :nextText= "$t('nextText')" 
+        v-model="pagination1" 
+        @change="pageChanged()"
+      ></van-pagination>
+      <pre>Page: {{pagination1.currentPage}} / {{pagination1.numPages}}</pre>
+    </demo-block>
+    <demo-block :title="$t('simpleMode')">
+      <van-pagination 
+        :totalItems="bigTotalItems" 
+        v-model="pagination2" 
+        :previousText= "$t('prevText')" 
+        :nextText= "$t('nextText')" 
+        mode="simple" 
+        size="small" 
+      ></van-pagination>
+      <pre>Page: {{pagination2.currentPage}} / {{pagination2.numPages}}</pre>
+    </demo-block>
+    <demo-block :title="$t('advancedUsage')">
+      <van-pagination 
+        :totalItems="bigTotalItems" 
+        v-model="pagination3" 
+        :showPageSize="showPageSize" 
+        :forceEllipses="true"
+        :previousText= "$t('prevText')" 
+        :nextText= "$t('nextText')" 
+      ></van-pagination>
+
+      <pre>Page: {{pagination3.currentPage}} / {{pagination3.numPages}}</pre>
+    </demo-block>
+  </demo-section>
+</template>
+
+<script>
+export default {
+  i18n: {
+    'zh-CN': {
+      simpleMode: '简单模式',
+      prevText: '上一页',
+      nextText: '下一页'
+    },
+    'en-US': {
+      simpleMode: 'Simple Mode',
+      prevText: 'Prev',
+      nextText: 'Next'
+    }
+  },
+
+  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
+    };
+  }
+};
+</script>
+
+<style lang="postcss">
+.demo-pagination {
+  .van-pagination {
+    margin: 5px 0;
+    width: 100%;
+  }
+
+  .van-doc-demo-block {
+    padding: 0 15px;
+  }
+}
+</style>