message: get/set_did_metadata String -> &cstr oops
diff: @@ -173,7 +173,7 @@ impl DidCommandExecutor {
  }
  DidCommand::GetDidMetadata(wallet_handle, did, cb) => {
  info!("GetDidMetadata command received");
  - cb(self.get_did_metadata(wallet_handle, did));
  + cb(self.get_did_metadata(wallet_handle, &did));
  }
  DidCommand::AbbreviateVerkey(did, verkey, cb) => {
  info!("AbbreviateVerkey command received");
  