Slider-type selector for demagnetization steps

[pont-us]

See correspondence with Rob Coe, July-August 2019, about his Triaxe files with ~500 (sic) demag steps. Easiest would be to implement the selector as a plot type rather than another Swing widget. I'm thinking of a horizontally elongated plot of vertical bars, with x position being step sequence number and y position being treatment level. Triaxe files seem to have multiple cycles of treatment so this will be useful. And show the intensity too?

Quick workaround for similar functionality: add an "always use sequence number" option for the demag plot.