MDL-23514 lang : Adding an option to force language of documentation links
MDL-42618 fix grade importing of whitespace idnumbers
MDL-41767 themes: Support for parent-specific sheets in plugins
MDL-41646 Wiki: Removed unnecessary wiki_info class
MDL-44066 caching Don't advertise session mode for MongoDB and memcached
MDL-43344 upgrade to latest Flowplayer
MDL-40921 mod_workshop: New events to replace add_to_log function calls.
MDL-40921 mod_workshop: Unit tests for new events system.
MDL-40921 mod_workshop: Alter event levels as requested by David.
MDL-44018 quesiton variant was not backed up or restored.
MDL-40061 mod_data: replaced 'view' add_to_log call with an event
MDL-40061 mod_data: replaced 'view all' add_to_log call with an event
MDL-43979 Javascript: Correct checking of attributes during dialogue init

Various dialogue attributes are optional and are provided by the parent and
not provided as attributes to the dialogue being initted.

As a result, if the setting is not provided during init, we were assuming
that the value would be false rather than checking the real attribute.
MDL-44055 mod_quiz: Add missing alternate name fields
MDL-44055 mod_glossary: Add missing alternate name fields
MDL-44079 Javascript: Check whether a dialogue is focused before closing
MDL-44079 Javascript: Closing a tooltip should pass event details
MDL-44079 Javascript: EditPDF editor should be modal
MDL-40921 mod_workshop: fix unit tests
MDL-39337 html_writer: Added img() function

img function has been added to the html_writer.
use it by calling the function as shown:
html_writer::img('foo.com','Foo',array('title'=>'Foo2'));
This will result in the following string:
<img src="foo.com" alt="Foo" title="Foo2"/>