Some refactoring of how handlers are handled, particularly with their default options. This is an unfortunately widespread change and will affect modules utilizing the API.

#261418: Make sure views cache is invalidated whenever the menu is rebuilt to catch some situations.

#259905: Use of isset instead of empty when exploding arguments caused the "" argument to turn into an invalid argument, causing validation to fail when combined with ajax paging.

#249934: Unfix the fix unfix fix unfix for views_get_current_view() which just generally hates references.

#256089: Drupal block delta has a limit of 32, but views could generate deltas longer than 32; this puts an md5 hash in for long deltas that keeps a conversion table.

#252970 by eaton and #250516 by RoboPhred: More stuff for statistics.module and default views for popular content

#239044: backlinks for search module; also, some cleanup to view export (this means all existing default views need to be re-exported to get this cleanup)

Various fixes, including making sure that exposed filter settings pass through to argument links and pager links.

A basic analyzer to help find problems, though it needs more analyzing. Plus, new theming information that will really help people figure out exactly what templates they can use to affect their output.

NEW: argument defaults and validation; pluggable. This will greatly ease some of the problems with argument discovery. We need to get a few more basic plugins written for this.

#241917 by John Morahan: Some menu alter stuff I left out of a previous patch. (This time for sure!)

#242388: (partially by John Morahan) Create a new display type whose sole purpose is to attach to another display on the view, thus allowing views within views. Like magical querying burritos.

#241917: (by John Morahan) -- allow two displays on the same view to have the same path, using access control to determine which view the user is given. This allows separate administrative views, for example.