Expose (basic version of) QwtPlotCurve through SIP binding, re #8912
clarify what type means in the doc of plotSpectrum, re #8912
Expose QwtData so we can get lines' x andy data, re #8912
A bit of doc, and many methods into __dir__ re #8912
First decent version of new CLI, still some TODOs, re #8912
Module doc, re #8912