It is now impossible to reduce the number of random vectors or moments.
It is also no longer possible to set the number of energy points used by
the method -- this can be supplied by providing a sequence of energies
when calling the KPM object. We replace the 'increase_energy_resolution'
and 'increase_accuracy' methods by 'add_moments' and 'add_vectors'.
The tests have also been updated to reflect these changes.