removed ABCMeta (field can already use metaclass)
= -> IN for subselect on m2m field
fixed denorm_rebuild for sum_field
one more fix
fixed bug with random actions order (action_set with ordered params crashed everything)
Sum will be 0 if no related field exists
added `exclude` to all Aggregate fields
added `exclude` to denorm_rebuild
travis fix
working exclude
fixed tests
fix for requirements
correct test runner
updated requirements
database requirements
mysql
maybe this helps
Fixed SumField in M2M fields
calculating sum for m2m relations
Fixed decrement