$page['where'] was an SQL clause used to retrieve pictures in #images
table. $page['items'] is the list of picture ids of the current section.
improvement: function initialize_category replaced by dedicated included PHP
script include/section_init.inc.php. Code was refactored to improve
readibility and maintenability. $page['navigation_bar'] is now build in
category.php instead of initialize_category function. Function check_cat_id
was also replaced by a piece of code in the new file. The file to include to
display thumbnails from category.php is now set in section_init.inc.php
instead of calculated in category.php.
bug fix: the test for rel="up" link for standard HTML navigation links in
category menu was not working with non numeric categories, such as
"favorites".
improvement: function check_login_authorization removed because useless but
in profile.php.
git-svn-id: http://piwigo.org/svn/trunk@1036 68402e56-0260-453c-a942-63ccdbb3a9ee
dac7decfb5