documentation mistakes in FileTask

No make method exists:

  t = FileTask.new
  File.exists?("path")                  # => false
  FileUtils.mkdir("path")               # will not be removed

  t.make("path/to/file.txt")
  FileUtils.touch("path/to/file.txt")
  File.exists?("path/to/file.txt")      # => true

  t.rm("path/to/file.txt")
  File.exists?("path")                  # => true
  File.exists?("path/to")               # => false