Changed code to be compatible with all versions.

- Patch #40886 by chx: fixed problem with recursive/nested node API calls manipulating the same array references.

- Patch #41109 by chx: fixed problem with _node_name() returning NULL instead of array() when there are no node types.

- Patch #40532 by wtanaka: use longblog for data in the cache.  Is reported to fix utf-8 problems and improves consistency with PostgreSQL.

  1. fixed problem with long URLs being truncated (and causing errors)
  2. added CREATE UNIQUE INDEX to prefix.sh
  3. changed totalcount from int to bigint to prevent overflow
  4. unifies index names, syncs with database.mysql

  Updated changelog.

- Modified patch #40534: improved themability of forum icons (makes it possible to use animated gifs) + removed forum setting.

- Patch #40393 by Richard: corrected permissions of menu/path settings on the content submission form.

- Patch #40524 by drumm: made sure that visiting the admin/modules page does not break your setup if you haven't run udpate.php yet.