fix: Transform modules via Babel to CommonJS instead of UMD

Author: nathanbuchar

babel.config.js

@@ -14,6 +14,6 @@ module.exports = {
   plugins: [
     '@babel/plugin-proposal-object-rest-spread',
     '@babel/plugin-proposal-class-properties',
-    '@babel/plugin-transform-modules-umd',
+    '@babel/plugin-transform-modules-commonjs',
   ],
 };

package-lock.json

@@ -39,7 +39,7 @@
     "@babel/core": "^7.1.6",
     "@babel/plugin-proposal-class-properties": "^7.1.0",
     "@babel/plugin-proposal-object-rest-spread": "^7.0.0",
-    "@babel/plugin-transform-modules-umd": "^7.2.0",
+    "@babel/plugin-transform-modules-commonjs": "^7.2.0",
     "@babel/preset-env": "^7.1.6",
     "@hellosign/eslint-config": "^1.4.0",
     "babel-core": "^7.0.0-bridge.0",