Correctly convert remote port bytecode to uint16 port number. (#321)

* Correctly convert remote port bytecode to uint16 port number.

Copied the network_to_host_short function from the ASIO library to convert the remote port byte code to a uint16 number.

* Switched from uint16_t to unsigned short to work in Windows

* Updated missed uint16_t to unsigned short

ixwebsocket/IXNetSystem.cpp

@@ -278,4 +278,17 @@ namespace ix
 #endif
     }
 
+    // Convert network bytes to host bytes. Copied from the ASIO library
+    unsigned short network_to_host_short(unsigned short value)
+    {
+        #if defined(_WIN32)
+          unsigned char* value_p = reinterpret_cast<unsigned char*>(&value);
+          unsigned short result = (static_cast<unsigned short>(value_p[0]) << 8)
+            | static_cast<unsigned short>(value_p[1]);
+          return result;
+        #else // defined(_WIN32)
+          return ntohs(value);
+        #endif // defined(_WIN32)
+    }
+
 } // namespace ix