Add minor comment for account updates
@@ -13,6 +13,7 @@ pub enum AccountUpdate {
Create { address: Address, nonce: Nonce },
/// Delete an existing account.
/// Note: Currently this kind of update is not used directly in the network.
+ /// However, it's used to revert made operation (e.g. to restore state back in time from the last verified block).
Delete { address: Address, nonce: Nonce },
/// Change the account balance.
UpdateBalance {
