added; local/remote_lat local/remote_thr perf test

@visionmedia I started implementing the zeromq performance test suite as defined [here](http://www.zeromq.org/results:perf-howto) for the node binding.  Some interesting results thus far.  I will probably continue to implemented inproc and perhaps other perf tests in this branch.

I used the python and lua bindings as a reference:
http://www.zeromq.org/bindings:lua