add agreementindex on family level to help guide taxonomist to bat families in need

[jhpoelen]

As suggested by @ajacsherman

most agreements between batnames 2023, MDD, HMW2019 on the family level.

Guiding question - which bat families have the least agreement and need attention of taxonomist?

[jhpoelen]

@ajacherman - can you check that consistent naming has been applied for family column label across the taxonomic resources you've aligned?

e.g., Family_HMW / Family_batnames2023