Update define_callbacks argument to avoid deprecation warning
Loose friendly_id version a bit for rails 4.1
Create real Order object in promotion_spec

See https://github.com/rails/rails/pull/13978

It looks like it broke rspec-rails stub_model implementation when
assigning that stub to its parent. (in a has many context)

A similar case also happens with mock_model (failing with *unexpected
message attribute*)