Use setImmediate reference of the context object.

Former-commit-id: 28c11df25ceb1a414caaa61eaee54fae27a2ff03

dist/lodash.js

@@ -152,6 +152,7 @@
         getPrototypeOf = reNative.test(getPrototypeOf = Object.getPrototypeOf) && getPrototypeOf,
         hasOwnProperty = objectRef.hasOwnProperty,
         push = arrayRef.push,
+        setImmediate = context.setImmediate,
         setTimeout = context.setTimeout,
         toString = objectRef.toString;