DamageMobj can destroy the damaged actor if the death state sequence has zero duration. But Actor.target is a garbage collected member variable, i.e. it will be null, once the actor it points to gets destroyed.
This was originally done correctly in the C++ code but during the scriptification all those 'AActor *target = self->target' lines were removed because they looked redundant, but were not.
- removed 'self' as a dedicated token. Internally this gets handled as a normal but implicitly named variable so the token just gets in the way of proper processing.
- removed P_ prefix from SpawnMissile export.
- fixed a crash with misnamed function exports.
- fixed a few problems that were encountered during conversion:
* action specials as action functions were not recognized by the parser.
* Player.StartItem could not be parsed.
* disabled the naming hack for PowerupType. ZScript, unlike DECORATE will never prepend 'Power' to the power's name, it always needs to specified by its full name.
* states and defaults were not checked for empty bodies.
* the scope qualifier for goto labels was not properly converted to a string, because it is an ENamedName, not an FName.
