PvP Toggle (no restart needed!)

With this mod, anyone who has the Privilege to kick players (moderators and admins have this ability) can call the following:
.pvpon
and
.pvpoff

This is a global toggle that prevents players from causing damage to others, the hit sound and red flash persists but no damage or knockback is taken. You do NOT need to change the config and restart anymore!

For this to work, you MUST NOT DISABLE PVP in the config!