Remote: Added URI into the error when connection to remote server fails.
Remote: Added URI into the error when connection to remote server fails.

Update issue 1334
Status: Done
Owner: pekka.klarck
Implemented this pretty much as proposed. After thinking this a little more, storing the URI in the library itself felt best, simply because it was anyway the only one who actually needed it. Decided to put it into a _private attribute anyway.

userzimmermann/robotframework-python3,userzimmermann/robotframework-python3,userzimmermann/robotframework-python3,userzimmermann/robotframework-python3,userzimmermann/robotframework-python3