First draft of benchmark infrastructure

* A generic makefile is used to automate the various compilation steps
  and benchmark automation
* Uses the julia code from the cython tutorial by Kurt W. Smith
* Benchmarks python, numpy, cython, numba, pythran
* Unfortunately, Parakeet chokes on np.int32
Add arc_distance micro-benchmark from https://bitbucket.org/FedericoV/numpy-tip-complex-modeling

* Parakeet chokes on the numpy.arctan2 function.
* Numba does not perform as well as expected (I must have made some mistakes).