Add require patch for node.js

js/append/require.js

@@ -0,0 +1,14 @@
+(function () {
+  // In node.js, the variable `r` below will be undefined after executing
+  // the following code:
+  //
+  // var obj = global;
+  // var arg = 'require';
+  // var r = obj[arg];
+  //
+  // One guess is that node.js uses special implementation of require.
+  // For this to work on webruby, we have to add the following patch.
+  if (!(typeof window === 'object')) {
+    global['require'] = require;
+  }
+}) ();