implemented member plot_args that over-writes the metadata with any optional input argument (previously this was part of the enforce_plot member); renamed optional arguments in enforce_plot to be called plot_*, in agreement with metadata; added or renamed default class values for the plot_* parameters
implemented member plot_args that over-writes the metadata with any optional input argument (previously this was part of the enforce_plot member); renamed optional arguments in enforce_plot to be called plot_*, in agreement with metadata; added or renamed default class values for the plot_* parameters

jgte/orb,jgte/orb,jgte/orb,jgte/orb,jgte/orb