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-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
Automatically generated installer lang files
MDL-10115 User profile: Allow full list of courses to be viewed on a user's profile
Merge branch 'master' into install_master
MDL-45445 events: trivial changes
MDL-45445 events: added missing 'relateduserid' validation
MDL-45445 events: added missing 'other' validation
MDL-45445 events: documented the additional validation
MDL-45445 events: added '(optional)' to event params where applicable
MDL-43835 phpunit: Create unique starting id's for sequences.

When all starting autoincrement ids are the same, it's difficult to detect coding and testing
errors that use the incorrect id in test calls.  The classic case is cmid vs instance id.
To reduce the chance of the coding error we start sequences at different values where possible.

OUBlog installation is the case that highlighted this as it inserts a sitewide course module
at install time and cmid <> instance id in most cases.
Automatically generated installer lang files
MDL-10115 User profile: Use moodle_url and html_writer::link for course links on user profiles
MDL-46013 theme: Uninstall theme unconditionally unsets configs
MDL-45941 implement support for message sending from DB transactions and fix other problems

This patch includes following fixes:
 - messages may be now sent when database transactions active
 - consistent return status on failure from message_send(), false is
   returned only when message not created in message(_read)? table,
   processor failure results in debugging message only and messages
   are not marked as read
 - message_sent is triggered always with id from message table
 - logic for marking messages as viewed was standardised
 - message_viewed event is triggered consistently
 - improved performance when fetching user preferences
 - full unit tests coverage for send_message() function
 - fixed multiple other smaller issues discovered by unit tests
MDL-45985 ddl: improve check_database_schema method in database_manager
MDL-45985 cli: add new cli tool for validation of database structure