Adding the ability to turn on or off profiling.  

We had a request from a client to be able to provide detailed profiling so that dynatrace can allow them to view the performance hits from queries.  The following code allows a client to send an X-ML-Profile header of "yes" to return back a multi-part response containing the original response and the profiling information for that response.  I threw it out there in case you through it might be worth while to put into the main Roxy trunk.