Added code to expose the persistence_diagram class, the bottleneck_distance function and the point class to python. Most of the commonly used methods for each class have been exported. The constructor for point now requires that a data argument be provided along with x and y coord. This needs to be made optional. The constructor for persistence_diagram could possibly be rewritten as well.

#include <utilities/log.h>

#ifdef LOGGING
static rlog::RLogChannel* rlFiltration =                    DEF_CHANNEL("topology/filtration/info", rlog::Log_Debug);
static rlog::RLogChannel* rlFiltrationDebug =               DEF_CHANNEL("topology/filtration/debug", rlog::Log_Debug);
#endif // LOGGING