[ticket/11620] Fix quotes in extract_hostname_test

PHPBB3-11620
[ticket/11620] Add commas in extract_page_test

PHPBB3-11620
[ticket/11620] Make testable_facade non-static, expand.

Make the class functions of testable_facade no longer static methods,
but a class based one and expand the methods to be filled in, in later commits.

PHPBB3-11620