INTER: liveview enhancemnts

Feedback:

- The y-axis displays the spectrum number relative to that section only (i.e. always starts again at 1). It would be helpful if it could display the actual spectrum (or detector) number related to the wiring table. Or at least an option to change the displayed axis to match this.
- The cuts displayed are a little confusing as they seem to be just for the single spectrum or time-bin associated with the cross line on the plot. How easy would it be to be able to have an option to select a region for these cuts (e.g. select a rectangle)? Don’t worry if this is very complicated or likely to slow it down.