PersonalPVP v1.5.0-SNAPSHOT: Status permissions.

Additions:
These permissions can now fix players to one PVP status:

personalpvp.always.on
personalpvp.always.off

To prevent buggy behaviour, by default players that have this permission cannot change their own status or have it changed by an admin or op unless one of these permissions is unassigned.
It is still good practice to remove those self-toggling command permissions (such as personalpvp.togglepvp) when fixing a player's status.

Changes:
1 minor performance improvement to help with reducing unnecessary RAM usage.

I have tested the basic functionality of this, so I'd say this is stable.