Merge pull request #16 from semteacher/master

Correct mistake in the email notification
Removed all language packs (apart from English), after submitting them to AMOS

In the future, all language strings should be downloaded automatically alongside core language packs
Fix the restoring of checklist items which are linked to other course modules
Update README + version number
Prevent 'non-static member' warnings for get_user_groupings
Prevent any warnings about missing 'grouping' value
Allow activities to be imported from section 0
Merge branch 'master' into 01-checkmark_detail_info

Conflicts:
	lang/ru/checklist.php
	lang/uk/checklist.php
Resolved: leave as exist. Other langs are deleted