Handle the connection error

[wujtruj]

Error occurs when network is unreachable

===DEVICE: fgt-test===
Traceback (most recent call last):
  File "./fgt-extended-utm-log.py", line 292, in <module>
    main()
  File "./fgt-extended-utm-log.py", line 264, in main
    connect(HOST, USER, PASS)
  File "./fgt-extended-utm-log.py", line 64, in connect
    ssh.connect(host, username=user, password=passw)
  File "/usr/lib/python2.7/site-packages/paramiko/client.py", line 236, in connect
    retry_on_signal(lambda: sock.connect(addr))
  File "/usr/lib/python2.7/site-packages/paramiko/util.py", line 278, in retry_on_signal
    return function()
  File "/usr/lib/python2.7/site-packages/paramiko/client.py", line 236, in <lambda>
    retry_on_signal(lambda: sock.connect(addr))
  File "/usr/lib/python2.7/socket.py", line 224, in meth
    return getattr(self._sock,name)(*args)
socket.error: [Errno 101] Network is unreachable