Changeset [f270936f99cdd22f3e0df55a9d45d413ef1f9ae1] by Tim Vergenz

Document return value for auto-saved state transitions

My team just ran into a bug that took a long time to track down where
an auto-saved state transition method unexpectedly swallowed
exceptions. Some documentation on the behavior would have saved a lot
of searching. :)
https://github.com/aasm/aasm/commit/f270936f99cdd22f3e0df55a9d45d41...