Enable the test code. (This WILL break horribly, but I can start collecting data on my scratch site.)

This branch is for a highly experimental test to see how performance, memory consumption, and stability is affected by relying more on node_load.
Hopefully, it will help identify bottlenecks in the existing code.

I have a feeling that by optimizing usage patterns (cough category_get_tree cough) and using better internal data structures, we can decrease complexity and improve speed.

Also fixed invalid HTML.

- #90145: backport.

module to Drupal 5. This commit upgrades all modules in the category
package, including:
  - category
  - category_display
  - category_export
  - category_legacy
  - category_menu
  - cac_lite
  - category_bulkedit
  - category_outliner
  - category_pathauto
  - category_transform
  - category_views

Cnid was gettting overridden with NULL in category_load(), which was stuffing up navlinks in category_display.

#70640: fix caching mechanism to work for PHP5. Goes some way towards fixing category_pathauto problems.

Fixed incorrect call to category_node_get_categories() that was causing problems with category_pathauto.

Output admin titles for containers in select lists, and use some spacing in between 'prev' and 'next' links in category_display.

Things are still very slow with 4,000+ categories, though. More work
needed on this.

with a zero-based index, rather than using the cids of parents as
index values.
- Changes to various parts of the category system to accommodate this
change, including category_menu, category_legacy, and the category
activeselect callback.
- Updated the taxonomy wrapper to convert the result of
category_get_parents() into its old form (to maintain full backwards
compatibility with taxonomy).

updates to core taxonomy and book modules since 5 Mar 2006.

- #74629 by KarenS and myself: using the 'taxonomy: terms for [container x]' field listing with a view in category_views shows nothing.

- Changed category_node_save() to flatten the category array before returning. As such, category_pathauto is now able to properly handle saving the alias for nodes with assigned categories (including with free tagging categories).

- Fixed parent selection not defaulting correctly when using the 'add child category' links.

#62540: fatal error on deletion of containers and categories. Apparently, taxonomy_get_vocabulary()'s return value now gets converted to an array before getting passed to hook_taxonomy. WhenTF did this happen, and whyTF? Anyway, the wrapper version now just returns an array directly, since none of the taxonomy code that uses the return val as an object exists in the wrapper.