refactor: Message config in VIP group

[HackerDevs]

• Refactored the Messages section in VIP group config
• Added DontBroadcast to disable native connect/disconnect messages appearing in chat.

Prev:

"Messages":{
   "ConnectChat":"VIP {playername} joined the server",
   "DisconnectChat":"VIP {playername} left the server"
}

Now:

"Messages":{
   "Chat":{
      "Connect":{
         "Enabled":true,
         "Message":"VIP {playername} joined the server",
         "DontBroadcast":true
      },
      "Disconnect":{
         "Enabled":true,
         "Message":"VIP {playername} left the server",
         "DontBroadcast":true
      }
   }
}