add "Activity timeout" to README.md

README.md

@@ -311,7 +311,7 @@ NLogger::setLevel(NLogLevel::Debug);
 
 Note: to use logging macroses you have to define `NLOGS_ENABLED`.
 
-#### Websockets transport
+### Websockets transport
 
 Nakama C++ client has built-in support for WebSocket. This is available on all supported platforms.
 
@@ -328,6 +328,18 @@ For more code examples, have a look at:
 * [NWebsocketCppRest](https://github.com/heroiclabs/nakama-cpp/blob/master/src/realtime/NWebsocketCppRest.h)
 * [NCocosWebSocket](https://github.com/heroiclabs/nakama-cocos2d-x/blob/master/example/Classes/NakamaCocos2d/NCocosWebSocket.h)
 
+#### Activity timeout
+
+Built-in websocket transport supports "Activity timeout" feature - if no any message received from server during "Activity timeout" then connection will be closed. Set 0 to disable this feature (default value).
+
+```cpp
+rtClient->getTransport()->setActivityTimeout(20000); // 20 sec
+```
+
+You can change ping period on server - `ping_period_ms` parameter:
+
+https://heroiclabs.com/docs/install-configuration/#socket
+
 ## Contribute
 
 The development roadmap is managed as GitHub issues and pull requests are welcome. If you're interested to enhance the code please open an issue to discuss the changes or drop in and discuss it in the [community chat](https://gitter.im/heroiclabs/nakama).