PIM-1647 Renamed batch into mass edit
PIM-1647 Added a mass edit group action
PIM-1647 Added groups validation after operation has been performed
PIM-1647 Fixed multiselect widget value setting in behat
PIM-1647 Selected a non variant group for the standard add to groups
scenario
PIM-1647 Fixed the common attributes list

Product::getValue() doesn't return false anymore when the attribute
cannot be found in the product attributes set.
Introduction of a Product::hasAttribute() method instead.
PIM-1647 Removed useless use statement
PIM-1647 Updated changelog
Merge branch 'master' into feature/pim-1647

Conflicts:
	CHANGELOG.md
PIM-1647 Globalized the mass edit product saving
PIM-1647 Updated add to group mass edit english labels
PIM-1647 Created a new ACL for adding products to groups action
PIM-1647 Fixed code standards
Merge pull request #585 from akeneo/feature/pim-1647

PIM-1647 [Mass Edit Action] Add products to groups