Fixed network layer doing delayed actor deletion

The delayed actor deletion was meant to be used during the logic calls,
to avoid modifying the container while it is being iterated. The
deletions happening from the network layer are not done while iterating
the set of actors, so it can delete immediately.

This fixes an issue where an NPC would disappear when changing
appearance on tmwAthena, because this was implemented as a remove + add,
which broke due to the delayed deletion.

Mantis-issue: 507