Improved session close log

The session closed log message has been expanded to include information about the device sending the TCP RST. The new log message session closed TCP [client | server] RST simplifies troubleshooting by indicating whether it was the client or the server that sent the TCP RST. Jan 12 13:51:04 user@host RT_FLOW: RT_FLOW_SESSION_CLOSE: session closed TCP SERVER RST: 30.0.0.2/54584->50.0.0.2/8081 None 30.0.0.2/54584->50.0.0.2/8081 None None None None 6 p1 green red 250003018 1(60) 1(40) 2 UNKNOWN UNKNOWN N/A(N/A) ge-11/0/0.0 UNKNOWN Jan 12 13:53:44 user@host RT_FLOW: RT_FLOW_SESSION_CLOSE: session closed TCP CLIENT RST: 30.0.0.2/46488->50.0.0.2/23 junos-telnet 30.0.0.2/46488->50.0.0.2/23 None None None None 6 p1 green red 240003072 2(100) 1(60) 2 UNKNOWN UNKNOWN N/A(N/A) ge-11/0/0.0 UNKNOWN