- Fixed the issue with first join permission feauture

- Added first join permission support
- Added an ability to hide gray messages about admin actions

- Added join-sound setting and an ability to set the sound which will be player when player joins the server
- Added leave-sound setting and an ability to set the sound which will be player when player leaves the server

- Added config autoupdate
- Small code refactoring
- Fixed disable-advancements feauture (now it works perfectly)