initial update

node_modules/zen-observable/scripts/build.js

@@ -0,0 +1,7 @@
+const { execSync } = require('child_process');
+const plugins = require('./babel-plugins');
+
+execSync('babel src --out-dir lib --plugins=' + plugins.join(','), {
+  env: process.env,
+  stdio: 'inherit',
+});