message: Add EXTVER in the peers UI to indicate support of EXTVERSION
  Show whether the peer connected to us supports the EXTVERSION service.
diff: @@ -1027,6 +1027,9 @@ QString formatServicesStr(quint64 mask, const QStringList &additionalServices)
  case NODE_NETWORK_LIMITED:
  strList.append("LIMITED");
  break;
  + case NODE_EXTVERSION:
  + strList.append("EXTVER");
  + break;
  default:
  strList.append(QString("%1[%2]").arg("UNKNOWN").arg(check));
  }
  