broken attempt to impute classes
imputing classes WIP but at least every Thing hatched

class hierarchy flat
Thing not shown in taxon_picker
some node coloring problems
full success gated by incomplete ontology
Thing now root of hierarchy WIP taxon_picker incompletely colored and buggy
converted all pickable .nq files WIP taxon_picker and sub/super overriding
WIP Taxon.get_instances() now hierarchic but clicking abstract taxons still weird
keep set_ and taxon_picker side-by-side