Javadoc
Initializes a plugin prior to the beginning of a game. The completedInits
parameter is the list of plugin role names that have been successfully initialized.
If sequence dependencies are satisfied (or if there are no sequence dependencies),
then an implementation must complete its pre-game initialization process and return
its role name. If sequence dependencies are not satisfied, then an implementation
must return null. It will be called again after additional successful initializations
have been completed. If initialization is not possible, then returning the string
'fail' will cause the server to log an error and shut down. This will be helpful
just in case the implementation also logs a detailed error message.