AModify.

See https://github.com/guttermonkey/play2-scala-todolist
See
http://53ningen.com/programming/play%E3%81%AE%E3%83%81%E3%83%A5%E3%83%BC%E3%83%88%E3%83%AA%E3%82%A2%E3%83%AB%EF%BC%9Atodo%E3%83%AA%E3%82%B9%E3%83%88%E3%82%92%E4%BD%9C%E3%81%A3%E3%81%A6%E3%81%BF%E3%81%9F