External Library Geodesic

Original library (published under MIT license):
http://code.google.com/p/geodesic/

We added a python wrapped and made small fixes to the original library, to make it compatible with cython.

To install this, either run 'pip install gdist' or download these
sources and run "python setup.py install" in current folder.

Python 2.7, Cython, and a C++ compiler are required.