Added method asStringState(StringConversion stringConversion).
Changed from StringConversion to StringConverter.
Remnoved "example" in the header printout.
Moved AddressState and PersonState from cdd.state to cdd.testgen.state + moved MutableState and ImmutableState from cdd.testgen to cdd.state.
Moved MutableStringState and InvalidStateException from cdd.testgen to cdd.state.
Added header.