Fix agent detection on Windows
Fix agent detection on Windows

The agent detection fails if you have a mingw setup with a working ssh-agent. The ENV SSH_AUTH_SOCK is set, but windows fails to use the UnixSocket class.

E, [2017-01-25T09:46:15.783805 #75060] ERROR -- net.ssh.authentication.agent[24dcda0]: could not connect to ssh-agent: uninitialized constant Net::SSH::Authentication::Agent::UNIXSocket
Did you mean?  Socket
               IPSocket
               UDPSocket

net-ssh/net-ssh