This is a bit of an odd commit: it adds a user_permissions table that
has capabilities that are not yet usable. Specifically, the table allows
setting DENY permissions as well as restricting permissions to an
individual group, but neither of those work yet. I want to make sure
that the existing, limited permission system seems to transfer over
properly before adding the additional complexity for those.
The Alembic data migrations for this commit is fairly ugly, but seem to
work okay.
Deimos
62b0adc983