Updated clusters to include altitude support

This breaks current code, but only small changes are needed.
Mostly: positions to create objects are always a tuple, not separate x,
y (and z).
Changed some of the class method names.
Try to make code more consistent between Detector/Station/BaseCluster.
Fixed ScienceParkCluster if 501 is not in stations.
Fix HiSPARCStations, n_detectors is now a function, not a property,
also add height support.
Fix HiSPARCNetwork, issue warning for missing station info, not an
exception.
Update tests to work with the new sapphire.clusters.