[ticket/12941] Add sami.conf.php for Travis CI.

PHPBB3-12941
[ticket/12941] Check for Sami parse errors on Travis CI.

PHPBB3-12941
[ticket/12941] Fix remaining Sami complaints.

PHPBB3-12941
Merge pull request #2849 from bantu/ticket/12941

[ticket/12941] Check for Sami parse errors on Travis CI.

* bantu/ticket/12941:
  [ticket/12941] Fix remaining Sami complaints.
  [ticket/12941] Check for Sami parse errors on Travis CI.
  [ticket/12941] Add sami.conf.php for Travis CI.