Use require, not import, for SVG renderer

src/SVGSkin.js

@@ -2,8 +2,7 @@ const twgl = require('twgl.js');
 
 const Silhouette = require('./Silhouette');
 const Skin = require('./Skin');
-
-import SvgRenderer from 'scratch-svg-renderer';
+const SvgRenderer = require('scratch-svg-renderer');
 
 class SVGSkin extends Skin {
     /**

src/util/svg-text-bubble.js

@@ -1,6 +1,5 @@
 const SVGTextWrapper = require('./svg-text-wrapper');
-
-import SVGRenderer from 'scratch-svg-renderer';
+const SvgRenderer = require('scratch-svg-renderer');
 const xmlescape = require('xml-escape');
 
 const MAX_LINE_LENGTH = 170;