These features were deprecated at least 3 minor releases ago. I found
one mistake which was that `z_validateaddress` had not been placed
behind the `addrtype` deprecated feature; this has been fixed.
Previously, `finalorchardroot` and `orchard.anchor` were serialized differently
in the RPC API, which made it difficult to correlate them. This changes the
serialization for `finalorchardroot` to match `orchard.anchor`.
Daira Emma Hopwood
Jack Grigg
Greg Pfeil
Greg Pfeil