Fix default settings for 'pantools group'
I discovered a problem with the way pantools group
is run with v4.2.0: having no arguments about relaxation causes PanTools to call the grouping "0" with: "grouping_v1, similarity: 0, inflation: 0.0, intersection rate 0.0, contrast: 0.0".
This is not what we want, users should always think about their grouping settings.
Therefore, this merge request requires users to specify: (--relaxation=<params> | [--contrast=<contrast> --similarity-threshold=<similarityThreshold> --intersection-rate=<intersectionRate> --mcl-inflation=<mclInflation>])