Bootstrap Enrichment Test For Enrichment And Depletion

[KevinMarinus]

Is your feature request related to a problem? Please describe.
When I do bootstrap enrichment tests I have for some particular usecases very strong enrichments for for example GABAergic neurons, which is accompanied by a negative 'stdevs from mean' for Glutamatergic (and/or non-neuronal) cell types - suggesting depletion for these cell types. However, this 'direction' is not tested for (nor automatically plotted; y>0).

Describe the solution you'd like
I'd like to be able to also test for this negative direction.

Describe alternatives you've considered
Although I can plot these negative values manually with ggplot, i don't have alternatives for testing it.

Additional context
Additionally, it would be nice to have a quick setting option for axes adjustments to adjust the standard bootstrap enrichment plots to negative directions and keep them consistent when making several plots.