* New button allows to create standard issuer for nextcloud
* Since the endpoints url has to be https and nextcloud relys on the
baseurl to create the endpoints, the baseurl of issuers has now to be
https as well (or empty).
* Google's baseurl was changed to https (there was no reason not to),
whereas Facebook and Microsoft baseurls remain empty.
* In case of the creation of a nextcloud issuer, the baseurl is
required.
* Nextcloud requires the baseurl, therefore a parameter is added to
create_standard_issuer($type, $baseurl = false). That parameter not
required (or used) for anything but Nextcloud.
We added 2 fields to the model and we needed to update the tests.
I also removed some error_log from the rest client (very useful while developing)
Part of MDL-58220
