MDL-40420: timemodified field update when lesson_page is updated
MDL-34989 assign: Allow students to submit when grade is overriden

Also inform teachers when grading is disabled due to gradebook lock/override.
MDL-34989 assign: Do not add a param to grading_disabled - cannot be backported.

Conflicts:

	mod/assign/locallib.php
MDL-27953 auth: allowed the LDAP plugin to be manually assigned to uploaded users
MDL-38758 mod_forum: fixed issue where pass by reference removal caused an undefined variable error
MDL-40933 Administration: Added 'is after' and 'is before' to date filter
MDL-40937 mod_assign - remove debugging code from 'previous submissions' javascript, that was breaking in IE8/IE9
MDL-35922 - Adding aria attributes to create-folder modal
MDL-40469 Gradebook: Fixed setType warning while exporting gradebook with publishing set
MDL-40662 block_course_overview: added addinstance capability to remove debugging message due to system context being used on the 'Default My home page'
MDL-35927 filepicker: add aria attribute to display modal error
MDL-40320 Course page: Text greyed when conditional activity available
Automatically generated installer lang files
MDL-36011 tablelib: Make column headers expand/collapse links accessible.

Conflicts:

	theme/base/style/core.css
	theme/bootstrapbase/style/moodle.css
MDL-40889 prevent 304 when minimising JS
MDL-31226: quiz: Fix message for attempts built on previous.

At the moment, when attempt is built on the last one, "not yet answered"
message is shown, which confuses many people. This patch modifies the state to
"complete" for attempt based on previous and modifies the output string.

Many thanks to Tim Hunt for guiding me through quiz infrastructure and some code
suggestions.
MDL-41002 fix typo causing fatal error on other users page

Credit goes to Bernhard Brandstetter, thanks!
MDL-34785 performance improvement with big list of courses
Merge branch 'wip-mdl-40933-m25' of git://github.com/rajeshtaneja/moodle into MOODLE_25_STABLE
Merge branch 'wip-MDL-34785-m25' of git://github.com/marinaglancy/moodle into MOODLE_25_STABLE