Changes

• Added lock and unlock commands to reroll.
• Added permission message when a player doesn't have permission to use the command.
• Refactored all 3 reroll commands into a single command.
• Remove useless aliases from reroll command.
• Fix lock command feedback to send the player name rather than the player entity.
• Change @Mod to use metadata from mcmod.info.
• Update mcmod.info with valid information.
• Add mod logo file.