Cleaned up Python bindings to restore functionality:
* StaticPersistence is iterable, its nodes are usable (sign, pair, cycle)
* StaticPersistence knows how to map its nodes into Filtration indices
* moved PythonCmp into utils.h
* minor cosmetic changes
#ifndef __PYTHON_ZIGZAG_PERSISTENCE_H__
#define __PYTHON_ZIGZAG_PERSISTENCE_H__
#include <topology/zigzag-persistence.h>
#include <topology/image-zigzag-persistence.h>
#include <boost/python.hpp>
//typedef int BirthID;
//typedef boost::python::long_ BirthID;
typedef boost::python::object BirthID;
typedef ZigzagPersistence<BirthID> ZZPersistence;
typedef ImageZigzagPersistence<BirthID> IZZPersistence;
#endif