Adding a warning (with the error message) when can't connect to a host. ...

...And adding the host name into the error message when failed.
We have a pending release (1.0.1) that does not admit ABI changes. After that we anticipate a 1.1.0 which would allow ABI additions, as this would be.

So I don't think it needs to go anywhere different, but I don't think we can merge this PR just yet.