Added separate DateTimeFilter with contains instead of equals filter. Added < > <= >= filters to DateFilter and DateTimeFilter. refs #15613
Added removeEmptyValues config to determine if empty values have to be included in query or not. refs #16418
Only make request if value is not empty. refs #12048
Updated habtm filter. refss #10411
Fixed strict error in HasAndBelongsToManyFilterSet.php