[EHN] including pre-processing adaptative threshold

[bruAristimunha]

list_of_norm_energy = sqrt(Total energy of EEG trial)/std(eegtrial)

sort_energy = sort(list_of_norm_energy)

Apply an adaptive threshold based on the session level.

From meeting with @Marco-Congedo, @qbarthelemy

[Marco-Congedo]

The adaptive thresholding method is described in this paper (see Fig. 3).

Here is the Julia code and its published documentation.