Resolve misconception with ODPOR pseudocode impl.
Like the SDPOR implementation before it, the ODPOR
implementation suffered from a similar fault in its
implementation. Determining whether an insertion was
necessary into a wakeup tree for some point in the
past requires determining whether the sleep set and
the set of weak initials overlap one another. If
their intersection is the empty set, THEN we attempt
to insert an actor. The prior implementation attempted
to find the first such actor that was not contained
in the sleep set, but this is semantically different
