Workaround to create a #Play2.1 #Json #Reads / #Writes in a companion object #scala (in #Play2.2, it's no more needed)

_LICENSE.txt

            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
                    Version 2, December 2004

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            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
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CODE.scala

case class Foo(bar: String)

// extends Function1 is just to workaround a limitation in Play2.1
object Foo extends Function1(bar: String, Foo) { 
  implicit val fmt = Json.format[Foo]
}