message: Modify the toHostAddr interface to support host resolved (gethostbyname).
  * Issue the "meta_server_addrs" in the configuration support the host name.
  Modify the toHostAddr interface to support host resolved (gethostbyname).
  * replace the gethostbyname with getaddrinfo.
  * Refactoring part of the code.
diff: @@ -214,7 +214,7 @@ int main(int argc, char *argv[]) {
  return EXIT_FAILURE;
  }
  - auto kvstore = initKV(peersRet.value(), hostAddrRet.value());
  + auto kvstore = initKV(peersRet.value(), localhost);
  if (kvstore == nullptr) {
  LOG(ERROR) << "Init kv failed!";
  return EXIT_FAILURE;
  