New special values for "domain" parameter
This MR is preliminary work for #3040 (closed)
it introduces new options for "domain":
- empty string: means cookies are only valid for the portal itself. This might be used in some extremely specific situations (SAML/OIDC/CAS only + no manager)
- #PORTAL#: use the same domain as the portal such as auth.example.com including subdomains
- #PORTALDOMAIN#: use the parent domain of the portal, such as example.com
Once #3040 (closed) is complete, this work will allow the cookie domain to be completely derived from $req
We could even already make #PORTALDOMAIN#
the default in new installs ? This way users will only have to change the "portal" variable in most situations.