PIM-2441: Fix UT for DateRangeFilter
PIM-2441: Add isset test
PIM-2430: Make works MetricFilter for isEmpty operator (ORM)
PIM-2430: Change baseData to null if data is null
Change filter config to add the 'empty' choice only when defined
Remove 'empty' option from product group filter
Add the empty choice to product value filters
Merge pull request #1038 from akeneo/PIM-2442

PIM-2442: Make empty filter works for Metrics ODM + ORM
Fix price filter to display currency when filtering by empty price
PIM-2434: Make price filter work for empty operator on ORM
PIM-2442: Fix metric filter for ODM
PIM-2442: Make Price filter work with empty operator on MongoDB
Merge pull request #1039 from akeneo/PIM-2442

PIM-2434: Make price filter work for empty operator
PIM-2442 : update changelog
PIM-1704 Implement UI for filtering products by identifier using 'in list' operator
Merge branch 'master' into ng