Merge pull request #53 from karl/feature-check-process

Check for existence of `process` before using it

src/lolex-src.js

@@ -405,9 +405,12 @@
         setInterval: setInterval,
         clearInterval: clearInterval,
         Date: Date,
-        hrtime: global.process.hrtime
     };
 
+    if (hrtimePresent) {
+        timers.hrtime = global.process.hrtime;
+    }
+
     var keys = Object.keys || function (obj) {
         var ks = [],
             key;