Ianoc/case class tuple converters

Tests won't pass as relies on macro code in an as yet un-released version of bijection
it would be nice to add a macro for:

`def fieldsOf[T: IsCaseClass]: Fields`
that returns a Fields object with the dotted names and the types set.

The goal is to use this with TypedDelimited and generate the types needed so cascading can parse the strings without storing strings in the tuples.