Enrichment vignette: change from pie-charting p-val to pie chart of -log(pval)

https://bioconductor.org/packages/release/bioc/vignettes/InterMineR/inst/doc/Enrichment_Analysis_and_Visualization.html#piechart-and-barplot-graphs

Pies and bar charts are pretty, but given the fact that a smaller P value is better, it takes some figuring out to understand what's going on - the smaller the pie segment / the smaller the bar, the more significant it is.

One option could be to subtract all the values from 1 so smaller values get bigger slices, but that would also require some explaining. I think it might make more sense just to remove these two visualisations.