public FileWatcher register(final Path path, final FileEventHandler handler) {
    return register(c -> path, p -> new FileEventOptions(p, handler), EMPTY);
  }
public FileWatcher register(final Path path, final FileEventHandler handler) {
    return register(c -> path, p -> new FileEventOptions(p, handler), EMPTY);
  }
public FileWatcher register ( final Path path , final FileEventHandler handler ) { return register ( c -> path , p -> new FileEventOptions ( p , handler ) , EMPTY ) ; }
Register the given directory tree and execute the given handler whenever a file/folder has been
created, modified or delete.

@param path Directory to register.
@param handler Handler to execute.
@return This module.
Register the given directory tree and execute the given handler whenever a file / folder has been created modified or delete .