MistTags v2.3.1 Beta

MistTags 2.3.1 Beta is a small permission visibility fix on top of 2.3 Beta.

Fixes:

• /mt help now only shows commands the sender has permission to use.
• /mt tab completion now only suggests commands the sender has permission to use.
• Standalone /addprefix, /addsuffix, /removeprefix, and /removesuffix tab completion now respects staff/self-service permissions.
• Self-service players with misttags.custom only see their own name as a target suggestion.