Insert sample 'default' URLs for the PDP endpoints in the HTTPS binding section

[davidjbrossard]

Issue #358 has 2 parts to it one of which is to add the 'regular' URLs as recommended. We closed the issue (bc the greater issue is solved via George's PR) but we still need to add sample URLs as guiding example.

[mtrimpe]

Each HTTPS binding currently also contains a SHOULD describing how the default URL should be formed by appending the default path to the base PDP URL.

See e.g. https://openid.github.io/authzen/#section-12.1.1-2

[julioauto]

Do the SHOULDs that Michiel is talking about cover this issue? Or are we looking for a reference table with all URLs listed? Something like that?

[mtrimpe]

It might actually be good to extract the common logic into a top-level section which also includes a table with the various calls and URLs.

I needed to do that for the Search APIs when adding pagination and I think it improved the section quite a bit.

I'll see if I can find the time to have a go at that.

[mtrimpe]

I've raised PR #379 with a generic section with an overview. It also removes JSON references from the Information Model to make that transport agnostic.

See this CodePen for the result.