Dragscroll possible, scroll the screen with the mouse at desktop view

- click on a empty list area and drag the view left/right to scroll

client/components/boards/boardBody.js

@@ -1,5 +1,6 @@
 import { ReactiveCache } from '/imports/reactiveCache';
 import { TAPi18n } from '/imports/i18n';
+import dragscroll from 'dragscroll';
 
 const subManager = new SubsManager();
 const { calculateIndex } = Utils;
@@ -219,6 +220,7 @@ BlazeComponent.extendComponent({
       boardComponent.openNewListForm();
     }
 
+    dragscroll.reset();
     Utils.setBackgroundImage();
   },