modules/jooby-filewatcher/src/main/java/org/jooby/filewatcher/FileWatcher.java
public FileWatcher register(final Path path, final Class<? extends FileEventHandler> handler) {
    return register(path, handler, EMPTY);
  }
public FileWatcher register(final Path path, final Class<? extends FileEventHandler> handler) {
    return register(path, 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.