PLF-5978 Groovy compilation exception while clicking on featured products from acme home page

Fix description: use PropertyValueComparator class from ECMS core utils.
Merge pull request #30 from exodev/fix/4.1.x/PLF-5978

PLF-5978 Groovy compilation exception while clicking on featured product...
PLF-5930: Use i18n keys for the tooltip in Details tab
Merge commit 'fa921be159868b1ac8a0b52890233755be4011ca' into HEAD