RFC: Fix kde plot
Fix for degenerate case where the factor-level creates a degenerate probability distro (all the same values).
Minor housekeep and reuse funcs from muttlib.utils instead of creating very similar ones.
Fix for degenerate case where the factor-level creates a degenerate probability distro (all the same values).
Minor housekeep and reuse funcs from muttlib.utils instead of creating very similar ones.