For a MizerParams() object, summary() prints the model metadata, size
grids, selected species parameters and fishing gear details. For a
MizerSim() object, it first prints the parameter summary and then reports
the simulated time period and output interval.
For ArraySpeciesBySize(), ArrayTimeBySpecies() and
ArrayTimeBySpeciesBySize() objects, summary() returns a small list with
the value name, units, dimensions and a per-species data frame containing
minimum, mean and maximum values. Printing that summary object gives the same
compact table in a human-readable form.