MDL-29004 Wiki: display images in printer-friendly view
MDL-35930 filepicker filemanaer: make announcement on page change when selecting view files options
MDL-40877 core_text: Added UTF-8 safe strrchr method
MDL-40447 Administration: Fix translation: "Profile" should be "Profile Fields" on advanced (more...) user filter form
MDL-41222 Remove unnecessary course cache rebuild
MDL-35925 - File picker - Adding aria attributes to assist in accessibility
MDL-36803 TinyMCE: Fix TinyMCE following touch events on iOS browsers
MDL-40877 repository_url: Use textlib functions instead of mb_strlen()
MDL-38765 quiz view: fix duplicate message.

The "No more attempts are allowed" message was being shown twice. I
checked back, and it has been like that since before the quiz was
converted to use a renderer. Still, it looks horrible, so changing it.
MDL-41366 qbehaviour_informationitem fix name capitalisation.
MDL-41387 tags: changed character case in string used when deleting a course
MDL-33472 google plugins: move helper functions to upgradelib.php

upgrade.php is reserved for the upgrade steps only. See also
MDL-34103
MDL-41401 backup: fix misnamed test method
MDL-41410 Caching: move comment to the appropriate place.

MDL-38162 fixes the issue about testing the connection to the memcached
daemon, which means testing once the connection to the pool of servers
and not to each of the servers while being added to the pool.
It misses to move the comment to that code too.
MDL-41249 assign: Restore step missing gradingform mapping

Thanks to Matthieu Raggett for the report and the solution.
MDL-41149 assign: Group submission updates emailed to wrong person

grade_item_update was altering the userid in the submission record
instead of cloning it. This meant only the last member of a group
recieved all notifications meant for other students in the group.
MDL-41175 themes: Add/remove group members page broken on small screens.
MDL-41213 filepicker: corrected outline of selected file dialogue
MDL-41106 cache: several fixes for the session cache.

This issue makes several fixes for the session loader and the session store.
 * maxsize argument now works for session caches.
 * fixed performance hole when interation occurs frequently.
 * fixed cache purge bug occuring when multiple caches are defined before being used.
 * improved lastaccess handling.

Big thanks to Marina who contributed the following commits:
 * Always make sure the elements in cache are sorted so we need to remove only elements in the beginning of array
 * Remove expired elements from session store to free memory
 * Minor bug fixes
MDL-41291 cache: Use fread to avoid race conditions