Business rule: License OwnerName can only be edited within SKU EditOwnershipDuration

When a license is created the name of the original owner is registered in License.OwnerName. For the duration defined in SKU.EditOwnershipDuration, this field can still be edited (by changing the name of the related Owning Customer?).

Once the duration has exired, this field is locked, providing an easy way for a human to check for consistency.