Add gender for new stuff.

I defaulted to 1:1.  As far as I know, while we may not know the exact
ratios for most new Pokémon, we do know that everything I just marked
1:1 comes in male and female.

Also, we need to split this into per-form for Meowstic's "forms".

Also also, wait, is gender_rate seriously not a foreign key?  I spent a
good minute trying to figure out where the gender ratio enum table was.