PIM-3236 : add a category filter in PQB and use it in filter bundle
PIM-3236 : add specs for PQB category filter
PIM-3236 : add specs for category filter (filter bundle)
PIM-3236 : update changelog

Conflicts:
	CHANGELOG.md
Merge pull request #1703 from akeneo/PIM-3236

PIM-3236 : add a category filter in PQB
Fix style and phpdoc
Refactor SequentialEditController
Merge pull request #1712 from akeneo/ci-fixes

Ci fixes
PIM-3237: Move filter transformation to catalog bundle
PIM-3237: Use constants to describe operators
PIM-3237: Add spec for orm
PIM-3237: Fix PR comments