Merge pull request #400 from GridSpace/3mf-import-fix

fix 3mf import

src/ext/jszip.esm.js

@@ -0,0 +1,7 @@
+/** Copyright Stewart Allen <sa@grid.space> -- All Rights Reserved */
+
+//import original library
+import * as JSZip from "./jszip.js";
+
+//export object attached to the window object
+export default self.JSZip;

src/load/3mf.js

@@ -3,7 +3,7 @@
 'use strict';
 
 import { THREE } from '../ext/three.js';
-import * as JSZip from '../ext/jszip.js';
+import JSZip from '../ext/jszip.esm.js';
 
 let { BufferAttribute, Matrix4 } = THREE;
 
@@ -218,7 +218,7 @@ function extractItems(records) {
  */
 export function parseAsync(data) {
     return new Promise(async (resolve, reject) => {
-        let zip = await JSZip.default.loadAsync(data);
+        let zip = await JSZip.loadAsync(data);
         let models = {};
         for (let [key, value] of Object.entries(zip.files)) {
             if (key.endsWith(".model")) {