Description: There would be a button next to the play like in hosted worlds to invite but instead it would be for invite to your current server.
The Attached Images show what it could look like in launcher and in game
In Launcher
First: If the server is in the server mappings
Second: IF the server is not in the server mappings (EG: Private SMPS etc)
In Game:
Third: If the server is in the server mappings