Enhance PSX with a way to calculate the peak threshold

[t-b]

epoch=[4000,6000]
sel=select(channels(AD9),[65,66],all)
sel65=select(channels(AD9),[65],all)
kernel=psxKernel($epoch,$sel, 0.6, 3, (-6))
peakThresh=0.04
lowFreq=550
highFreq=0

psxPrep(psx(duck, kernel, peakThresh, lowFreq, highFreq), sdThresh = 4.2)

The psxPrep operation will work on sweepDataFiltOffDeconv, create a histogram from it (all points histogram) and fit that. See https://www.cell.com/biophysj/fulltext/S0006-3495(12)00935-6 and the existing code like PSX_FitHistogram and PSX_CreateHistogramOfDeconvSweepData.

Needs graph B and C from page 1433 (all points hist and gaussian fit). Y-axis of all points hist and x-axis of fit should not be in SD but in deconvolved wave y units.

Show both the histogram and the gaussian fit.

Add marker to highlight the sdThresh value so that the user can then see the value for peakThresh to use for the psx operation.

[t-b]

• Draft looks good
• Use 3 significat digits for writing theta into the legend
• Use marker with good trace name for store
• Concatenate multiple waves as input and only create on hist/fit/marker line
• Use 2.5 as sdThresh