[ticket/11543] Add unit tests for obtain_guest_count()

PHPBB3-11543
[ticket/11543] Add unit tests for obtain_users_online()

PHPBB3-11543
[ticket/11543] Add unit tests for obtain_users_online() with empty forum

PHPBB3-11543
[ticket/11543] Add unit tests for obtain_users_online_string()

PHPBB3-11543
[ticket/11543] Use correct IP addresses and inject time for correct values

PHPBB3-11543
[ticket/11543] Add more users so #hidden <> #normal

PHPBB3-11543
Merge remote-tracking branch 'remotes/nickv/ticket/11543' into develop-olympus

# By Joas Schilling
# Via Joas Schilling
* remotes/nickv/ticket/11543:
  [ticket/11543] Add more users so #hidden <> #normal
  [ticket/11543] Use correct IP addresses and inject time for correct values
  [ticket/11543] Add unit tests for obtain_users_online_string()
  [ticket/11543] Add unit tests for obtain_users_online() with empty forum
  [ticket/11543] Add unit tests for obtain_users_online()
  [ticket/11543] Add unit tests for obtain_guest_count()