Hook 'metadata_hosted' and 'frontpage' are no longer called so do
not register hooks for them. Update the docs. Remove useless call
to configpage hook on admin module Test page (likely a copy-paste
error).

Sometimes we patch or edit a hook to meet our specific needs.
Somtimes this leaves behind a file like FILENAME.orig. The hook
detection login still runs these other files, making for confusing
debugging issues. Use a stricter match on what makes a valid hook name
to avoid these issues.

PSR-12 compliancy