PokemonSpecies.form_description -> PokemonFamily.description.
More prep for combining the Nidoran and Volbeat/Illumise families.
Again, not strictly necessary. The justification is that families will
need a description and having both columns is silly.
Had to combine a few descriptions. Shellos & Gastrodon and Deerling &
Sawsbuck were easy since they were almost duplicates anyway (supporting
the merge!). Burmy & Wormadam were less similar, so i just pasted them
together. They could probably use a rewrite.
