Feature/connection state (#25)

* (cmake) add a warning about 32/64 conversion problems.

* fix typo

* New connection state for server code + fix OpenSSL double init bug

* update README

ixwebsocket/IXWebSocketTransport.h

@@ -148,7 +148,7 @@ namespace ix
         mutable std::mutex _lastSendTimePointMutex;
         std::chrono::time_point<std::chrono::steady_clock> _lastSendTimePoint;
 
-        // No data was send through the socket for longer that the heartbeat period
+        // No data was send through the socket for longer than the heartbeat period
         bool heartBeatPeriodExceeded();
 
         void sendOnSocket();