Issue #1355798 by Kjartan, xjm: Fixed Installer on PHP <5.3 results in parse error instead of warning about old php.

#38278 by edkwh and Kjartan. Don't offer the impossible option of filtering on nodes with two types.

Upload.module
- Fixing a bug caused by the PHP5 patches.
Beware: PHP4's array_merge() will silently accept objects and convert them to arrays. We should not depend on this behaviour in the future.

File.inc / file-using modules:
- Removing the constant FILE_SEPARATOR: forward slashes work fine on Windows, and it was being used incorrectly as an URL separator sometimes.
- Adding @ to mkdir and chmod to supress ugly PHP errors. They are already reported with drupal_set_message().
- Fixing default for variable 'file_directory_temp'.
- Clarifying the help tip for 'file_directory_temp' in admin > settings.

  correctly.

- Patch #5526 by Kjartan: cleaned up node_page(), show a 404 when the node
  could not be found.

  bootstrap code.  Patch by Kjartan.

 - Adds drupal_set_header() and drupal_get_headers().
 - Cache now stores custom headers.
 - Replace theme_head() with drupal_get_html_head(), added drupal_set_html_head().
 - Added RSS autodiscover links to node, blog and taxonomy pages.

- Many excellent news aggregator improvements by Kjartan:
    + Added drupal_http_request().
    + Replaced rssfeeds with OPML feed subscription list.
    + Added support for pubDate.
    + Added support for conditional gets using ETag and Last-Modified.

- Patch #4858: search module did not remember the search filter.  Patch by
  Kjartan.

- Made it possible to set and display multiple status messages.  Modified patch by
  Kjartan.

- Fixed glitch with form_radio().  Reported by Kjartan.

- Made the chameleon theme display comment authors.  Patch by Kjartan.

- Removed some dead code and improved the link emission.  Patch by Kjartan.

- Added file handling.  Work by Kjartan.

Patch by Kjartan:
  - Adds possibility to hide menu item when it has no children. (Fixes the
    node/add problem when user doesn't have access to create any node
    types.)
  - More doxygen comments.

 + Simplified cache logic in drupal_get_path_map().
 + Added check to see if errors should be reported to error_handler().
 + Use proper db_query() syntax in throttle(), and use $_ENV instead of
   getenv().
 + Changed fix_gpc_magic() to use array_walk (C functions will always be
   faster), and renamed _fix_gpc_magic_array() to _fix_gpc_magic().
 + Renamed $node in array2object() to $array.
 + Renamed $node in object2array() to $object.
 + Minor other coding method tweaks.

  + Changed drupal_page_header(): converts the If-Modified-Since header into a
    timestamp and compares against the cache data.  Ignore If-Modified-Since
    and ETag headers if they are present but empty.

  + Few minor other code cleanups.

- Fixed race condition in session handler.  Patch by Kjartan.

- Tidied up the DoxyGen comments.  Patch by Kjartan.

- Admin module clean-up.  Patch by Kjartan.  (The status function should be
  a theme_ function really.)

User module patch by Kjartan:

- Optimized user_external_load(), only need to fetch the data once.
- Removed unused functions:
  user_get()
  user_set()
  theme_menu_list()
- Fixed user_validate_name() to not accept \.
- Modified user_validate_name() to use alnum, which varies depending on
  the system locale.
- Optimized user_validate_name() to not use unnecessary regular
  expressions.
- Optimized user_access() by using less logic to fetch permissions and
  cache.
- Removed uncessary logic from user_deny().
- Fixed user_fields() to properly cache $fields.
- Optimized user_set_authmaps() to not perform unnecessary queries.
- Removed return value from user_set_authmaps().

- Bugfix: fixed typo in cloud module.  Patch by Marky.

- Bugfix: fixed menu glitch in book module.  Patch by Kjartan.

- Improvement: made it possible to disable the comment controls and reworded some of the configuration settings.

- Improvement: removed a left-over from Drupal 4.2.0 (dead code).

- Improvement: replaced hard-coded XHTML around the XML icons with class="xml-icon".

- Improvement: removed the custom navigation menus shown at the top of the "user information page" and integrated them in the new navigation block.  The "my account" link in the navigation menu will unfold.  Also removed the "delete account" link/functionality (for now).

- Improvement: fix for "magic quotes" settings.  Patch by Steven.  I also removed check_php_settings().

- Improvement: block themability improvements.  Modified patch from Ax and Steve/CodeMonkeyX.

- Fixed bug #2617: editing user information does not work.  Patch by Kjartan.

- Bugfix: fixed SQL errors with tablesort when 'order' is invalid.
  Patch by Kjartan.  Fixes bug #2613.

- Bugfix: fixed problem with search key replacement.  Patch by Kjartan.

- Help system improvements: eliminated the _system hook.  Patch by Michael.

- Bloggerapi module fixes.  Patch by Kjartan.

- Coding style fixes.  Patch by Michael.

- Fixed book preview problem.  Patch by Kjartan.

- Performance improvement: removed redundant inner join.   Patch by Kjartan.

- Block module fixes.  Patch by Kjartan.

- Made the check for If-Modified-Since and Etag headers work for non-Apache
  webservers.  This will, for example, improve caching on IIS.  Patch by
  Kjartan.

- Committed Al's new admin link texts.  Remarks:

  1) As explained by Al, there is still a glitch with the 'create content'
     menu.
  2) The user module part of the patch did not apply due to Kjartan's earlier
     patch.

   + Fixed CSS to use the same format as the rest of drupal.css.
   + Added fallback routine for menu icons.
   + Fixed anonymous users not seeing the menu.
   + Added proper access checks for admin and help menu items.

- Tested and committed Kjartan's performance patches.  (Fixed the access check
  in update.php though.)

- Bugfix: fixed broken links in the emitted RSS feed discovery code.  Modified
  patch by Kjartan.

- Small corrections and improvements to the INSTALL file.  Patch by Kjartan.

- Bugfix: fixed the CREATE FUNCTION in database.mssql as it needs to be prefixed with GO for some obscure reason.  Patch by Kjartan.

- Bugfix: fixed the defaults for blocks in database.mssql so the NOT NULL fields get values.  Patch by Kjartan.

- Bugfix: changed check_form() to use htmlspecialchars() instead of drupal_specialchars() as this caused Drupal to emit incorrect form items in presence of quotes.  Example:

  <input type="submit" class="form-submit" name="op" value="Submit "top nodes" block changes" />

  IMO, drupal_specialchars() is better called xmlspecialchars() to avoid confusion.

- Bugfix: when an anonymous user visits a site, they shouldn't see any content (except the login block, if it is enabled) unless they have the "access content" permissions.  Patch by Matt Westgate.

- Improvement: improved the error checking and the error messages in the profile module.  Updated the code to match the Drupal coding conventions.  Modified patch from Matt Westgate.

- Improvement: don't generate the <base href=""> tag in the base theme; it is already emitted by theme_head().  Patch by Kristjan.

- Improvement: don't execute any SQL queries when checking the permissions of user #1.  Patch by Kjartan.

- Improvement: made a scalable layout form that works in IE and that behaves better with narrow themes.  Part of patch #51 by Al.

- Improvement: removed some redundant print statements from the comment module.  Modified patch from Craig Courtney.