add isIE in instance

packages/artplayer/src/index.js

@@ -189,6 +189,10 @@ export default class Artplayer extends Emitter {
         return utils.isSafari;
     }
 
+    get isIE() {
+        return utils.isIE;
+    }
+
     get proxy() {
         return this.events.proxy;
     }

packages/artplayer/src/utils/compatibility.js

@@ -2,3 +2,4 @@ export const userAgent = typeof window !== 'undefined' ? window.navigator.userAg
 export const isMobile = /Android|webOS|iPhone|iPad|iPod|BlackBerry|IEMobile|Opera Mini/i.test(userAgent);
 export const isSafari = /^((?!chrome|android).)*safari/i.test(userAgent);
 export const isWechat = /MicroMessenger/i.test(userAgent);
+export const isIE = /MSIE|Trident/i.test(userAgent);