Feature request

Feature description

Separate permission for multiverse.signportal.create, so that players need permission to make nether portal types, and different permission for sign only portals, as they currently share the same permission, I would like the possibility so that signs only placed on nether portals work so players cannot place signs randomly on the floor.

How the feature is useful

This would be useful so that there is a requirement for players to assign signs to portals only for those that want to make a nether hub using this feature, we can prevent random signs placed on the floor and keep portals concise.
Portal <----> Portal.