public static Bundle Append(this Bundle bundle, Interaction interaction)
        {
            // API: The api should have a function for this. AddResourceEntry doesn't cut it.
            // Might TransactionBuilder be better suitable?

            Bundle.BundleEntryComponent entry;
            switch (bundle.Type)
            {
                case Bundle.BundleType.History: entry = interaction.ToTransactionEntry(); break;
                case Bundle.BundleType.Searchset: entry = interaction.TranslateToSparseEntry(); break;
                default: entry = interaction.TranslateToSparseEntry(); break;
            }
            bundle.Entry.Add(entry);

            return bundle;
        }