Rename object id hydrator
Define hydrator as services
Inject hydrator in mass action handler
Fix PMD
Inject hydrator service
edefine product hydrator service id and class param
Update CHANGELOG
Merge pull request #917 from akeneo/mass_action

Mass action
Move handler to its own directory
Update CHANGELOG.md
Remove useless use statement
Redefine handler services
Merge pull request #919 from akeneo/mass_action

Mass action
Fix Attribute FQCN
Merge branch 'master' into flexible/repository

Conflicts:
	CHANGELOG.md