Add setImmediate (#40)

setTimeout, setInterval, setImmediate and their clear counterparts are
globals in Node. Because set/clearImmediate are not available in all
browsers, adding them here.

Author: jscissr

index.js

@@ -41,6 +41,12 @@ var defaultVars = {
     Buffer: function () {
         return 'require("buffer").Buffer';
     },
+    setImmediate: function () {
+        return 'require("timers").setImmediate';
+    },
+    clearImmediate: function () {
+        return 'require("timers").clearImmediate';
+    },
     __filename: function (file, basedir) {
         var relpath = path.relative(basedir, file);
         // standardize path separators, use slash in Windows too

readme.markdown

@@ -1,7 +1,7 @@
 # insert-module-globals
 
 insert implicit module globals
-(`__filename`, `__dirname`, `process`, `global`, and `Buffer`)
+(`__filename`, `__dirname`, `process`, `global`, `setImmediate`, `clearImmediate` and `Buffer`)
 as a browserify-style transform
 
 [![build status](https://secure.travis-ci.org/browserify/insert-module-globals.png)](http://travis-ci.org/browserify/insert-module-globals)