Improve error message / debugging options when ODIbot fails to automatically retrieve resources

[PietroLiuzzo]

If I go to the home page of ODI and click Create New Certificate
whatever I do, adding the URL or skippling the step, I get an error. latest attempt got me this error identifier 000574b8-cbb7-5ed6-6d6f-dc3a4c3b635f

The url where I describe our data is this
http://betamasaheft.eu/lod.html

and I honestly do not know why it is not fine.
We are trying to share as much and as openly as possible our data, and we would like to get a certificate. Any suggestion on how to make that better is more than welcome

thanks for any help

[olivierthereaux]

I think this is a similar issue to the one now documented at #1695.

[olivierthereaux]

In #1695 we have identified a recurring issue with the automated checker being blocked from requesting the webpages about the datasets. We have created a workaround for that which works in a number of cases we have identified, but does not seem to work for the URI mentioned by the OP here.

I recommend that we address, at some point, the fact that /app/controllers/response_sets_controller.rb is really fragile when it comes to error recovery, masquerading any type of issue with a rather unhelpful 404. And reflect that in the UI by giving a clearer error message (currently asking in somewhat passive-aggressive fashion why the URI is not valid).