refs #487: remove some unused configuation entries from fixtures

 SEARCH_ENGINE_FRIENDLY_URLS
 SHOW_VERSION_UPDATE_IN_HEADER
 PHPBB_LINKS_ENABLED
 ENTRY_NICK_MIN_LENGTH
 MAX_MUSIC_GENRES_LIST
 MAX_RECORD_COMPANY_LIST
 MAX_DISPLAY_RECORD_COMPANY_NAME_LEN
 MAX_DISPLAY_MUSIC_GENRES_NAME_LEN
 STORE_PAGE_PARSE_TIME
 STORE_PAGE_PARSE_TIME_LOG
 STORE_PARSE_DATE_TIME_FORMAT
 DISPLAY_PAGE_PARSE_TIME
 STORE_DB_TRANSACTIONS
 GZIP_LEVEL
 SESSION_WRITE_DIRECTORY
 SESSION_FORCE_COOKIE_USE
 SESSION_RECREATE