Updated panels_load_include() to prevent the re-inclusion of already-loaded include files. Hackish, but eh.

Major cleanup, moved several more functions out to include files, removed some crufty ones. Also refactored the master loader itself some more.

Got rid of a leftover use of $panel_page->pid, and updated the alternate admin menu structure to the current approach.

Moved panels_page_access() and panels_page_get_title() into the read inc; also made temporary modifications to the former that (hackishly) cope with the pre-emptive access checking on all links.

Stupid (evidently) unncessary call to panels_context_load_contexts() seems to have been the whole problem. Contexts are now being loaded properly...YAAAAAAAR!!!!!!!

This means we may well be ready for the first alpha release...

Some refactoring, partially to accommodate changes suggested by douggreen. The basic context-loading problem has not yet been solved, however.

by douggreen: re-added missing callback property to the validate function. Might actually not be necessary...we'll see.

by douggreen: Removed additional t() calls; added str_replace() to exporter to match coding standards.

Save routines should now pretty much be functional. The problems appear to now pretty much be limited to context loading/generation at render time. It's not clear if the problem is with panels_page logic, the Panels engine, or some squirrely D6 changes.

Changed name of argument error code constants slightly; added brackets in panels_load_include() for clarity.

Fixed an old error code constant; relocated the handlers to higher up in the file; moved sanitizer back into this main file, other odds and ends.

Updated function signatures to include $subtype as first parameter; also cleaned up repetitive copy/pasted docblocks on many render callbacks.

Docblock updates and changes in code style for references to match merlin's ($a = &$b instead of $a =& $b)