message: nonce serialization
diff: {
  "types": [],
  "structs": [{
  + "name": "nonce",
  + "base": "",
  + "fields": [
  + {"name":"value", "type":"string"}
  + ]
  + },{
  "name": "transfer",
  "base": "",
  "fields": [
  },{
  "name": "claimrewards",
  "type": "claimrewards"
  + },{
  + "name": "nonce",
  + "type": "nonce"
  }
  ],
  "tables": [
  