Advance the OfferingID only when the OfferingDesc has a meaningful update

Only advancing the OfferingID when OfferingDesc has a meaningful update. As I understand it, the current practice is to advance the OfferingID whenever the MeasDescription text changes from one measure package version to the next.

For PY026 measure package, updates to MeasImpactType and DelivType fields should not result in new OfferingIDs for offerings that are otherwise the same.