Fix permission Bug.

I updated the Plugin for the Minecraft Version 1.21 and JDK 21.

Update the plugin completly.

You can use now different chat channels.

Team: /tc <message> Permission: teamchat.use
Supporter: /sc <message> Permission: teamchat.supporter
Moderator: /mc <message> Permission: teamchat.moderator
Developer: /dc <message> Permission: teamchat.developer
Admin: /ac <message> Permission: teamchat.admin
Owner: /oc <message> Permission: teamchat.owner

Github: https://github.com/phillipunzen/Minecraft_TeamchatPlugin