message: add back button to saves
diff: @@ -1859,6 +1859,8 @@ void WiFiManager::handleWifiSave() {
  page = getHTTPHead(FPSTR(S_titlewifisaved)); // @token titlewifisaved
  page += FPSTR(HTTP_SAVED);
  }
  +
  + if(_showBack) page += FPSTR(HTTP_BACKBTN);
  page += FPSTR(HTTP_END);
  server->sendHeader(FPSTR(HTTP_HEAD_CORS), FPSTR(HTTP_HEAD_CORS_ALLOW_ALL)); // @HTTPHEAD send cors
  @@ -1885,6 +1887,7 @@ void WiFiManager::handleParamSave() {
  String page = getHTTPHead(FPSTR(S_titleparamsaved)); // @token titleparamsaved
  page += FPSTR(HTTP_PARAMSAVED);
  + if(_showBack) page += FPSTR(HTTP_BACKBTN);
  page += FPSTR(HTTP_END);
  HTTPSend(page);
  