MDL-45579 group: Prevent duplicate enrolment keys in course groups
MDL-45579 group: Behat tests to cover group enrolment key rules
MDL-29708 Fixed extra slashes in $string['storedfilenotcreated'].
MDL-29708 Fixed file_exception() arguments in rename().
MDL-45418 Files: Adding publisher docs to Filetypes
MDL-45418 Files: Adding upgrade steps for publisher docs

Conflicts:
	lib/db/upgrade.php
	version.php
MDL-45943: Replacement for publisher icons
Merge branch 'MDL-45418_27' of git://github.com/stronk7/moodle into MOODLE_27_STABLE
Merge branch 'MDL-45579-27' of git://github.com/FMCorz/moodle into MOODLE_27_STABLE
MDL-45808 group: Observe the group key policy upon group creation
Merge branch 'm27_MDL-29708_Typo_Extra_Slashes' of https://github.com/scara/moodle into MOODLE_27_STABLE
MDL-45763 question: fix SQL syntax for Oracle
MDL-39726 backup: fix SQL syntax for Oracle
MDL-39726 backup: fix SQL syntax for Oracle
MDL-45763 Question types: Allow saving '0' as question text.
MDL-44871 Behat: Add tests for Atto functionalities (some of them)
MDL-44871 Atto behat tests: Modified the tests to work around focus bugs with workspaces

The main changes here are that the "select the text in" step was modified to select only the
first text node in the editor field, and to focus on it's parent instead of the entire editable div.

Some tests had to be modified to match the new behaviour, and another "real" bug was found in the table plugin.
MDL-44871 Atto: Move custom select text step to atto specific step definition.
MDL-44871 Atto behat: Use one less page load to get to profile edit page
MDL-44871 behat: Hack to make equation editor visible