Compile bug (#122)

* 1) IXWebSocketTransport: BUG: int type has no warranty of number of bits. It depends on compiler and architecture. In my system (64 bit) is 32 bit.
1 << 63 is bad idea in this case because the final number is 0 by overflow.
The symptom observed is that the server can't receive messages.

2) IXSocketFactory: Compilation Warning: Variable not in use.

* Better aproach suggested by Benjamin.

ixwebsocket/IXSocketFactory.cpp

@@ -31,6 +31,7 @@ namespace ix
                                          std::string& errorMsg,
                                          const SocketTLSOptions& tlsOptions)
     {
+        (void) tlsOptions;
         errorMsg.clear();
         std::shared_ptr<Socket> socket;
 

ixwebsocket/IXWebSocketTransport.cpp

@@ -543,7 +543,7 @@ namespace ix
             }
 
             // Prevent integer overflow in the next conditional
-            const uint64_t maxFrameSize(1 << 63);
+            const uint64_t maxFrameSize(1ULL << 63);
             if (ws.N > maxFrameSize)
             {
                 return;