This release teaches "RuleBasedStateMachine" to avoid checking
"invariant()"s until all "initialize()" rules have been run. You can
enable checking of specific invariants for incompletely initialized
machines by using "@invariant(check_during_init=True)" (issue #2868).
In previous versions, it was possible if awkward to implement this
behaviour using "precondition()" and an auxiliary variable.
The canonical version of these notes (with links) is on readthedocs.