I'm running into this with the automated tests and the fixtures I think
sometimes using large auto-generated IDs?
But the point is, our tables generally use Rails's default `:integer`
size for its IDs, and then columns that reference them are *smaller*,
which is… not correct stuff, y'know?
So I figure, let's just expand the columns. We don't have enough data
that being real picky about the integer sizes matters, so let's keep it
simple and more obviously correct.
