Improve the error message when the value of a feature has not the right type
Problem seen with the cdpsm file sent on 15/05/2018 by N. Evreux (the first Asset.AssetContainer value is an Asset, not an AssetContainer)
Problem seen with the cdpsm file sent on 15/05/2018 by N. Evreux (the first Asset.AssetContainer value is an Asset, not an AssetContainer)