MDL-45645 mod_lti Add custom LTI request parameter ext_user_username
MDL-45764 mod_lti: Fix adding General Tool

This error only occurs when a ltisource
plugin is present that implements the
get_types callback.
MDL-45870 mod_assign: Outcomes are saved for each group member
MDL-35648 adding missing distinct selector in sql on participation report
MDL-45507 theme_bootstrapbase: Fix regression for theme based custom menu

in renderers/core_renderer.php.
MDL-38693 themes: amended z-indexes

Amended #dock z-index level from 11000 to 5000 across all themes; amended z-index style of #page-header in Overlay theme such that elements no longer occlude TinyMCE.
MDL-44929 Javascript: Import YUI 3.17.2
MDL-45803 mod_quiz: added attempt snapshot for the attempt and preview started events
MDL-45803 mod_quiz: prevented the attempt_started event from being triggered twice
MDL-45611 Questions: Fixing the layout of the 'points box'
MDL-45719 mod_lti - Pass language strings to inline JS to allow for escaping
MDL-42531 assign: refactor batch operations to use forms properly

Avoids a lot of ugly optional_param() use. Also fixes the
non-functional cancel buttons.
MDL-45935 tests: Specify step names during backup/restore tests
MDL-45870 mod_assign: Behat test covering some outcome usage
MDL-45803 mod_quiz: removed usage of the function quiz_fire_attempt_started_event
MDL-45803 mod_quiz: removed the quiz_fire_attempt_started function

Also commented in mod/quiz/upgrade.txt to inform developers.
Automatically generated installer lang files
MDL-45395 lib: Removal of excel 5 spreadsheet creation files.

The excel 5 writer files were using OLE licensing which is GPL incompatible.
These classes are not used in core.
MDL-10115 User profile: Allow full list of courses to be viewed on a user's profile
MDL-45970 quiz editing: fix display of random questions.

The pass by reference meant the function was clobbering the variable in
the calling function. Once that was change, it was not strictly
necessary to rename the variable in the function, but I did anyway for
clarity.

Thanks to Rajesh Taneja for finding the problem, and identifying which
bit of code was broken. I really just made the patch.