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
	lib/db/upgradelib.php
	version.php
MDL-45943: Replacement for publisher icons
Merge branch 'MDL-45418_26' of git://github.com/stronk7/moodle into MOODLE_26_STABLE
Merge branch 'MDL-45579-26' of git://github.com/FMCorz/moodle into MOODLE_26_STABLE
MDL-45808 group: Observe the group key policy upon group creation
Merge branch 'm26_MDL-29708_Typo_Extra_Slashes' of https://github.com/scara/moodle into MOODLE_26_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-42835 Scorm: Fix for JS error because no nodes are selected in the toc.
MDL-45808 enrol_self: Fixed behat to observe the group key policy

Conflicts:
	enrol/self/tests/behat/self_enrolment.feature
Merge branch 'MDL-42835-26' of http://github.com/damyon/moodle into MOODLE_26_STABLE
weekly release 2.6.3+