* Made the profiler work in HipHop:

* Made the profiler work in HipHop:
** Don't try to set a global variable in the same file as a class definition (Profiler.php). Set it in WebStart.php instead.
** In StartProfiler.sample, don't use require_once() to get ProfilerStub.

* Removed the setproctitle() stuff from ProfilerStub, the extension is not maintained and doesn't work with Apache 2.x
* Added an optimisation to wfProfileIn() and wfProfileOut() to reduce the overhead when profiling is not enabled
* Added the ability to configure in StartProfiler.php whether CPU time or wall-clock time is used, avoiding recompilation