ssh: enable `ssh_config=True` to default to `~/.ssh/config`
ssh: enable `ssh_config=True` to default to `~/.ssh/config`

Instead of specifying the path to `ssh_config`, a user can just use
`True` to use the default path.

lightlu/ncclient,ncclient/ncclient,vnitinv/ncclient,leopoul/ncclient,GIC-de/ncclient,earies/ncclient,nnakamot/ncclient,kroustou/ncclient,cmoberg/ncclient,einarnn/ncclient,nwautomator/ncclient