npc.php: add missing include
npc.php: add missing include

We need to include `RouteGenerator.class.inc` because there is a
serialized instance of `MultiPortRoute` that we get from the
database, and this class can't be autoloaded since it's not in its
own file.

smrealms/smr,smrealms/smr,hemberger/smr,hemberger/smr,hemberger/smr,smrealms/smr,hemberger/smr