For the moment, more relevant results (biologically speaking) without dilatation/erosion.

EROSION/DILATATION during connexion: added possibility to choose between 2 erosion conditions. The strict one seems to be best (strict_erosion=True)

solved BIG BUG: tangency of extensions and connexions leading to "deskeletonization" and sklgraph incoherence with python objects

+ under dev: delete too big extensions

* ellipsoid axes sorted in croissant order
* other parameters adjusted

added soma features (volume + working on best fitting ellipsoid axes) + modified skl brick.edge algo to support None value for calculus of edge lengths

+ nutrimorph.py setting

STEP1 of GRAPH EXTRACTION: Storage of adjacent extensions end points to somas into ext_root [[coord: tuple{3}, idx: int]]