MDL-47316 mod_forum: Fix course overview performance

 make more efficient use of mod_info cache by processing courses
 sequentially.

Change-Id: I03b808c8a7efc42879ec2689fbd2a9fe7a8f1103
MDL-47428 language: fixed typo
Automatically generated installer lang files
MDL-46391 messages: Display search button under contact list.

Add search button to only Message navigation -> Contacts section.
MDL-46054 web_services: bug fix in core_user_get_users

Thanks to Mikko Rantanen for the patch
MDL-46054 web_services: wrong key in exception string
MDL-46054 web_services: Fixed invalid parameter definitions
MDL-46978 gradebook: Edit grade item changes visibility of category
MDL-46282 core: Add VERP API

This issue is a part of the MDL-47194 Task.
This issue is a part of the MDL-39707 Epic.
MDL-47301 libraries: Update Typo3 to v4.7.19
MDL-47301 libraries: Patch Typo3 for Moodle's use
MDL-47474 Calendar export: Fix user id in authorization check
MDL-42993 auth: spaces removed from usernames by default only

Functionality by default does not change with this patch.
However spaces are no longer stripped when cleaning usernames IF
$CFG->extendedusernamechars has been set.

Also included 2 trim statements where small issues were found with reading
external usernames in that  were not filtered for trailing whitespaces.
Merge branch 'MDL-46282-master' of git://github.com/andrewnicols/moodle

Conflicts:
	version.php
MDL-47303 libraries: import latest jQuery library and friends
MDL-47477 libraries: use smoothness theme for jquery ui
Merge branch '47428-28' of git://github.com/samhemelryk/moodle
MDL-47404 filelib: Prevent flash from treating files as uploads
added to send_stored_file as well.
Merge branch 'master_MDL-47404' of https://github.com/danmarsden/moodle
MDL-37707 mod_assign: Prevent user from changing grouping in team submissions