Adds profiler tracing to presto output
Adds a class to make basic profiling easy.
Issue #47. Updated to treat tracked profile data as structs.
Issue #47. I have moved away from the toggle on/off approach and now provide static methods track (for initial) stop, and restart. Also exposes a static accessor for a given keyed thing being tracked.
Issue #47. Updated to only add profiler output to trace if some exists. Also changed trace kkeyinng for the profile data.
Merge pull request #48 from robotpony/profiler

First pass of profiler for presto