feat(page): add pull-to-refresh and back-to-top component

1. enable pull-down refresh for the target page in pages.json
2. add scroll mixin and back-to-top component for form and formdata pages, show back-to-top button when scrolling down

pages_tool/form/form.vue

@@ -14,11 +14,15 @@
 
         <loading-cover ref="loadingCover"></loading-cover>
         <ns-login ref="login"></ns-login>
+        <to-top v-if="showTop" @toTop="scrollToTopNative()"></to-top>
     </view>
 </template>
 
 <script>
+    import scroll from '@/common/js/scroll-view.js';
+
     export default {
+        mixins: [scroll],
         data() {
             return {
                 id: 0,