Socket leak on failed connection attempt

Start a standalone server and connect to it a client which issues put() calls in a loop. Kill the server. Restart the server. After restart the client won't be able to connect to the server.

The problem seems to be triggered by a socket leak. When the server is back up the client fails to obtain a socket to connect to it.

Might be also the cause of: https://github.com/infinispan/cpp-client/issues/150