message: Update CHANGELOG for Bech32.decode
diff: - @cosmjs/cosmwasm: Rename `SigningCosmWasmClient.signAndPost` method to
  `.signAndBroadcast`.
  - @cosmjs/demo-staking: Remove package and supporting scripts.
  +- @cosmjs/encoding: Add `limit` parameter to `Bech32.encode` and `.decode`. The
  + new default limit for decoding is infinity (was 90 before). Set it to 90 to
  + create a strict decoder.
  - @cosmjs/launchpad: Rename `CosmosClient.postTx` method to `.broadcastTx`.
  - @cosmjs/launchpad: Rename `SigningCosmosClient.signAndPost` method to
  `.signAndBroadcast`.
  