sam method in VolcanoPlot checking Log2(x) with incorrect condition

[steph-robinson]

alphapeptstats/alphastats/plots/VolcanoPlot.py

Line 152 in 89843be

if self.dataset.preprocessing_info["Normalization"] is None:

Hi, I noticed this line in the sam method of VolcanoPlot.py checks normalization status of the processing info instead of the Log2 status:

Here's what I suggest it to be instead:
if self.dataset.preprocessing_info['Log2-transformed'] is False:

Additionally, this method doesn't allow s0 to be defined by user, and instead defines constants within itself. Could this be added for users trying to call a moderated t-test and SAM FDR method?