Updated old user management routes to only be accessible with permission
to manage users, so also removed old content controls checking for that
permission.
- Removed uneeded custom refresh or logout actions for OIDC.
- Restructured how the services and guards are setup for external auth
systems. SAML2 and OIDC now directly share a lot more logic.
- Renamed any OpenId references to OIDC or OpenIdConnect
- Removed non-required CSRF excemption for OIDC
Not tested, Come to roadblock due to lack of PHP8 support in upstream
dependancies. Certificate was deemed to be non-valid on every test
attempt due to changes in PHP8.
- Primarily moved and re-organised view files.
- Included readme within views to document the convention.
- Fixed some issues with page field select list in previous commit.
- Tweaked some route names while going through.
- Split some views out further.
Closes#2805
