Change the way the extra bindings for the generic representation are generated
This ticket serves to record an email conversation in which it was agreed that:
The extra bindings generated for the generic representation should come from
genInst, and not from
GHC.Typesshould not import
GHC.Generics; instead, the generic representation for
GHC.Typestypes should be in
GHC.Generics(using standalone deriving where necessary).