* add set_hostname_addr_map to WebSocketClient
* add WebSocketTest unit test cases
* SpecifyServerIPAddress_AnotherHostname
* SpecifyServerIPAddress_RealHostname
* Change wrong_ip from 0.0.0.0 to 192.0.2.1
Use 192.0.2.1 (RFC 5737 documentation address) to ensure it acts
as a non-routable address and does not alias to loopback.
* Fix style check
* set short timeout in WebSocketTest.SpecifyServerIPAddress_RealHostname
cannot reach wrong_ip
