Correct the README

GUI is in an extra project
If a http.Head fails, try a http.Get before reporting an issue
AN001, AN002: Also get the publisher information

Required to set cross-keys for redis
Add AN003:  Which Datasets could not be retrieved by the URL and why
A couple of additions

* Make use of the publisher information
* Set appropriate cross-links for redis
* Somewhat simplify code calling of helper-functions (get rid of them)