Bug in GetBalanceAt -

[tjayrush]

This code

// TODO: BOGUS - THIS IN MEMORY CACHE IS GOOD, BUT COULD BE BINARY FILE
key := fmt.Sprintf("%s|%d", addr.Hex(), bn)
conn.cacheMutex.Lock()
var ok bool
if balance, ok = conn.balanceCache[key]; ok {
	conn.cacheMutex.Unlock()
	return balance, nil
}
conn.cacheMutex.Unlock()

must use chain in the cache's key otherwise things like Khedra will not distinguish between say gnosis and mainnet.