Update CHANGELOG with London changes overview

Author: fselmo

CHANGELOG

@@ -1,5 +1,21 @@
+v0.6.0-beta.1
+-------------
+
+Released 2021-10-22
+
+- Features
+
+    - London support (https://github.com/ethereum/eth-tester/pull/206)
+	    - Upgrade py-evm to v0.5.0-alpha.1 for London support
+	    - Default to London
+	    - Support access list transactions and dynamic fee transactions
+	    - Transaction param support for `access_list`, `type`, `max_fee_per_gas`, `max_priority_fee_per_gas`
+	    - Transaction receipt param support for `type` and `effective_gas_price`
+	    - Block param support for `base_fee_per_gas`
+
 v0.5.0-beta.4
 -------------
+
 Released 2021-04-12
 
 - Features