build: release 1.3.1

Author: fengyuanchen

CHANGELOG.md

@@ -1,6 +1,6 @@
 # Changelog
 
-## next
+## 1.3.1 (Dec 9, 2018)
 
 - Emulate click (single tap) and double click (double tap) in touch devices to support backdrop and image zooming (#210).
 - Ignore pointer events when not the primary button was pressed (#221).

README.md

@@ -791,7 +791,6 @@ All events can access the viewer instance with `this.viewer` in its handler.
 
 > Be careful to use these events in other component which has the same event names, e.g.: [Bootstrap](https://getbootstrap.com/)'s modal.
 
-
 ```js
 let viewer;