MDL-22950 adding new component column to the files table, unfortunately this change requires changes in all 2.0dev code, please review all custom code that was already upgraded to 2.0; fixing multiple problems and regressions in mod/assignment

MDL-21782 reworked enrolment framework, the core infrastructure is in place, the basic plugins are all implemented; see the tracker issue for list of unfinished bits, expect more changes and improvements during the next week

AMOS START
    MOV [sendcoursewelcomemessage,core_admin],[sendcoursewelcomemessage,enrol_self]
    MOV [configsendcoursewelcomemessage,core_admin],[sendcoursewelcomemessage_desc,enrol_self]
    MOV [enrolstartdate,core],[enrolstartdate,enrol_self]
    MOV [enrolenddate,core],[enrolenddate,enrol_self]
    CPY [welcometocourse,core],[welcometocourse,enrol_self]
    CPY [welcometocoursetext,core],[welcometocoursetext,enrol_self]
    MOV [notenrollable,core],[notenrollable,core_enrol]
    MOV [enrolenddaterror,core],[enrolenddaterror,enrol_self]
    MOV [enrolmentkeyhint,core],[passwordinvalidhint,enrol_self]
    MOV [coursemanager,core_admin],[coursecontact,core_admin]
    MOV [configcoursemanager,core_admin],[coursecontact_desc,core_admin]
    MOV [enrolledincourserole,core],[enrolledincourserole,enrol_manual]
    MOV [enrolme,core],[enrolme,core_enrol]
    MOV [unenrol,core],[unenrol,core_enrol]
    MOV [unenrolme,core],[unenrolme,core_enrol]
    MOV [enrolmentnew,core],[enrolmentnew,core_enrol]
    MOV [enrolmentnewuser,core],[enrolmentnewuser,core_enrol]
    MOV [enrolments,core],[enrolments,core_enrol]
    MOV [enrolperiod,core],[enrolperiod,core_enrol]
    MOV [unenrolroleusers,core],[unenrolroleusers,core_enrol]
AMOS END

By the way, the current style of creating course_sections is ugly. We
should probably have something like
make_sure_that_at_least_default_section_exists($courseid, $sectionid=null)
and not to insert it into database at many places as we do now.

course-section MDL-22262 Added a summaryformat field to the database and implemented it when editing/viewing sections and backup

This patch also implements a course renderer.

hub server MDL-19311 add some code to the index page to display the hub course list in case the hub plugin is installed + improve community block search form (subject + language)

navigation MDL-22425 Restructured navigation for the nth time plus performance tweaking and course display limit

MDL-21655 big scary enrolment and roles improvements - see tacker for list of changes, includes other minor fixes too

MDL-21233 moodle_url improvemewnts, code simplification, more diagnostics; fixed several regressions

MDL-20790 more page layouts -see base theme for full list; also added new css body class for describing current layout; base layout is now default for beter BC; require_login() now sets 'incourse' layout automatically

MDL-20204 first batch of major theme changes, some regressions are still there, expect more changes and improvements soon; see tracker for details and list of subtasks

This patch introduces two new blocks global_navigation_tree and settings_navigation_tree
both of which have been designed to make full use of the new navigation objects available through
the $PAGE object.
Bulk of this code is within lib/navigationlib.php

1. button_to_popup_window
2. link_to_popup_window
3. print_single_button
4. print_spacer
5. print_file_picture (deprecated)
6. print_user_picture
7. print_png (deprecated)
8. helpbutton
9. doclink
10. print_paging_bar
11. notice_yesno

Also fix redirect, so 303 redirects don't need to fully initialise $OUTPUT.

MDL-19010 fixed redirect at main page if upgrade required, otherwise it would end with exception due to DB structure changes

The code to print blocks in now in theme layout.php files. (Or in
moodle_core_renderer::handle_legacy_theme)

Code for printing blocks everywhere else has been stripped out.
(Total diffstat 1225 insertions, 2019 deletions)

The way the HTML for a block instance is generated has been cleaned
up a lot. Now, the block_instance generates a block_contents
object which gives a structured representation of the block,
and then $OUTPUT->block builds all the HTML from that.

How theme config.php files specify the layout template and block
regions by page general type has been changed to be even more flexible.

Further refinement for how the theme and block code gets initialised.

Ability for scrits to add 'pretend blocks' to the page. That is,
things that look like blocks, but are not normal block_instances.
(Like the add a new block UI.)

Things that are still broken:
 * some pages in lesson, quiz and resource. I'm working on it.
 * lots of developer debug notices pointing out things that
   need to be updated.

Also, part of the change from weblib.php functions to $OUTPUT-> methods.

This is part of http://docs.moodle.org/en/Development:Theme_engines_for_Moodle%3F

This is a big change, and the result is not perfect yet. Expect some debugging output
on some pages.

The main part of these changes are that $OUTPUT->header now looks for a file
in the theme called layout.php, rather than header.html and footer.html. Also
you can have special templates for certain pages like layout-home.php. There is
fallback code for Moodle 1.9 themes, so they still work.

A few of the old arguments to print_header are no longer supported. (You get an
exception if you try to use them.) Sam H will be cleaning those up.

All the weblib functions that have been replaced with $OUTPUT-> have version in
deprecatedlib, so existing code will go on working for the foreseeable future.

Start calling $PAGE->set_url in all the places it will be necessary
Start of a stub implementation of $PAGE->blocks to stop other things breaking
Remove some of the special case methods in admin_page

The new names are documented on
http://docs.moodle.org/en/Development:Convert_Draftarea_Files

"FORUM/MDL-14860, hide unsubscribe link if users are not allowed to unsubscribe from this forum, merged from 1.9"