This is for those situations where something basically impossible happens,
like $context->contextlevel not having one of the valid value, and you
want to throw an exception (for example in the default: case of a switch)
rather than just ignoring the possibility.
* Note: this would never lead to problems with default role definions.
* Also ended up mostly rewriting delete_category_form to simplify the messages that are displayed.
* New helper function require_all_capabilities, a bit like require_any_capability.
* Rewrite all the forms to use formslib and improve usability.
* Put the place where admins need to go to process approvals in the admin menu.
* Show the request course/pending requests button on the page for the category that requested courses get added to.
Bugs: MDL-17479, MDL-16426, MDL-16063, MDL-16013, MDL-15658, MDL-15556, MDL-15161, MDL-14925, MDL-13742, MDL-11557.
* Simplify category editing permissions to just moodle/category:manage and moodle/category:seehiddencategories.
* Enforce those correctly. (Note MDL 17502 is still outstanding.)
* Don't screw up category sort order when you just edit name or description.
* Niceties like where redirects go when you cancel or submit forms.
* Make sure a global course creator can see the site admin block.
* Don't allow a category to be made the child of one of its children!
* General code cleanup to bring key files more in line with best pracitice.
Apologies for the fact it is one big patch, rather than a series of smaller patches. However, categoryedit.php, category.php and index.php where in pretty bad shape and needed significant cleaning up. categoryedit.php, in particular, was almost completely rewritten.
Merged from MOODLE_19_STABLE.
* New basic define roles mode, with just an Allow checkbox for each capability.
* Button to toggle this form to/from advanced mode.
* Also, a separate mode for viewing a role definition, rather than just showing disabled checkboxes.
* Now duplicating a role just takes to you a pre-populated add role form, so you can double-check things before saving the new role.
* Deleting a role is now logged.
* Role reordering code cleaned up.
* You can now no longer delete the last role that has admin permissions.
* This includes a general refactor of manage.php, which eliminates manage.html, and splits of define.php.
skodak