Update SSH default options to permit agent forwarding

ansible.cfg

@@ -120,6 +120,7 @@ nocows = 1
 # Leaving off ControlPersist will result in poor performance, so use 
 # paramiko on older platforms rather than removing it
 #ssh_args = -o ControlMaster=auto -o ControlPersist=60s
+ssh_args = -o ControlMaster=auto -o ControlPersist=60s -o ForwardAgent=yes
 
 # The path to use for the ControlPath sockets. This defaults to
 # "%(directory)s/ansible-ssh-%%h-%%p-%%r", however on some systems with