This is a rewrite of the 'simulated backend', an implementation of the ethclient interfaces
which is backed by a simulated blockchain. It was getting annoying to maintain the old
version of the simulated backend feature because there was a lot of code duplication with
the main client.
The new version is built using parts that we already have: an in-memory geth node instance
running in developer mode provides the chain, while the Go API is provided by ethclient.
A backwards-compatibility wrapper is provided, but the simulated backend has also moved to
a more sensible import path: github.com/ethereum/go-ethereum/ethclient/simulated
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Co-authored-by: Felix Lange <fjl@twurst.com>
Co-authored-by: Gary Rong <garyrong0905@gmail.com>
