Add some comment for delegate cell lock

gwos/contracts/delegate-cell-lock/src/entry.rs

@@ -8,6 +8,12 @@ use ckb_std::{
 
 use crate::error::Error;
 
+/// A simple lock that delegates verification to another lock via a
+/// delegate-cell. This is supposed to be used on the rollup cell to support
+/// changing block producer key by e.g. multisig. In a production deployment,
+/// the delegate cell is supposed to be a type-id cell with a multisig lock, and
+/// delegates to secp256k1/blake160 lock with the current block producer key.
+///
 /// Lock args: type hash (and usually type-id) of delegate-cell.
 ///
 /// Delegate-cell data should be blake160 hash of a lock script.