Added the underscore node_module.

node_modules/underscore/amd/before.js

@@ -0,0 +1,18 @@
+define(function () {
+
+  // Returns a function that will only be executed up to (but not including) the
+  // Nth call.
+  function before(times, func) {
+    var memo;
+    return function() {
+      if (--times > 0) {
+        memo = func.apply(this, arguments);
+      }
+      if (times <= 1) func = null;
+      return memo;
+    };
+  }
+
+  return before;
+
+});