Creates and registers a world with its group, initialising its terrain, registering events, commands and tasks.
the WorldInfo of the created world or null if the a world with the same name already exists.
server.addWorld("world42"); // normal world server.addWorld!CustomWorld("custom", 42); // custom world where 42 is passed to the constructor
See Implementation
Creates and registers a world with its group, initialising its terrain, registering events, commands and tasks.