Added pan + zoom to diagram viewer; show_diagram() didn't return; added PyQt, PyOpenGL, NumPy as dependencies in the docs
#include <topology/chain.h>
#include "static-persistence.h"
#include "dynamic-persistence.h"
namespace dionysus {
namespace python {
typedef SPersistence::Chain VSPChain;
typedef DPersistenceChains::Chain VDPChain;
} } // namespace dionysus::python