MDL-44991 Behat: step to check if attribute does not contain text

The step checks that an attribute exists, but doesn't contain the
specified text.

Example:
Then the "class" attribute of "#mydiv" "css_element" should
not contain "accesshide"
MDL-45148 unit testing: pass role id instead of user id
MDL-45109 - theme/bootstrapbase - Fix Unordered and Ordered lists in RTL mode
MDL-44950 logstore_database: Make all settings positive for usability
MDL-45075 mod_forum: Move user subscription to an observer

The forum subscription function is called in some cases on forum creation
(specifically the case of an automatically subscribed forum).

Since the forum subscription requires both the course_module instance, and
the context these must both be present when subscribing users to the forum,
however these are not fully set up until after the forum has been created.

By moving the subscription to a subscriber, we are able to hook into the
module creation event after the course_module and context have been linked
to the forum instance.
MDL-45008 atto_link: Standardise unlinking for non-selections

When placing the cursor within a link, but not making a selection, we
should unlink the whole link.
MDL-45194 assign_feedback: Cache was never set and used in is_enabled
MDL-44855 AJAX: Arrays and Objects should be defined in the initializer

JavaScript is a prototypal language and complex types should be defined as
null in the prototype, and set up in the initializer instead.
MDL-45226 AJAX: Backport upstream bug fixes from YUI

This backports the following two patches:
* https://github.com/yui/yui3/issues/1757
* https://github.com/yui/yui3/issues/1778
MDL-45203 implement new event user_password_updated
Merge branch 'MDL-45226-master' of git://github.com/andrewnicols/moodle
Merge branch 'w17_MDL-45203_m27_loginlog' of https://github.com/skodak/moodle
MDL-45172 block_completionstatus: added a check for an empty string before appending
MDL-45216 events: Update to core/event/manager to return observer information.
MDL-45216 events: Unit tests for core/event/manager.

This includes unit tests for the new method get_all_observers
and updates to other methods that have been updated.
MDL-45218 events: New static methods for getting general event information.

New methods are get_static_info() and get_explanation().
MDL-45219 remove old assignment course instance list
MDL-45219 add \mod\chat\course_module_viewed event
MDL-45219 add report_viewed event to tool_capability
MDL-45219 add report_viewed event to report_questioninstances