update changelog for rpc api changes (#824)

* add cmd flag for rpc api modules

* add rpc-api flags

* improve test by fixing race condition by sleeping

* edit changelog

Author: araskachoi

CHANGELOG.md

@@ -35,7 +35,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 # Changelog
 
-## Unreleased
+## [v0.4.1] - 2021-03-01
 
 ### API Breaking
 
@@ -44,7 +44,6 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ### Bug Fixes
 
-
 * (evm) [\#760](https://github.com/cosmos/ethermint/issues/760) Fix Failed to call function EstimateGas.
 * (evm) [\#767](https://github.com/cosmos/ethermint/issues/767) Fix error of timeout when using Truffle to deploy contract.
 * (evm) [\#751](https://github.com/cosmos/ethermint/issues/751) Fix misused method to calculate block hash in evm related function.
@@ -58,6 +57,9 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (evm) [\#674](https://github.com/cosmos/ethermint/issues/674) Reset all cache after account data has been committed in `EndBlock` to make sure every node state consistent.
 * (evm) [\#672](https://github.com/cosmos/ethermint/issues/672) Fix panic of `wrong Block.Header.AppHash` when restart a node with snapshot.
 
+### Features
+* (api) [\#821](https://github.com/cosmos/ethermint/pull/821) Individually enable the api modules. Will be implemented in the latest version of ethermint with the upcoming stargate upgrade.
+
 ## [v0.4.0] - 2020-12-15
 
 ### API Breaking