[withProperties] More simple exporting my own types

[abdennour]

This resolves handling own types , however , it does not taske benefits of groovy extra-features comparing with Java .

My suggestion is to use Closures directly :

def withProperties=['name',{it.currency.displayName}]

Instead of :

creating whole class+ Instantiate it like this .

def withProperties = ['name', new CurrencyGetter('price.currency')]