This change makes the legacy transaction pool use of `uint256.Int` instead of `big.Int`. The changes are made primarily only on the internal functions of legacypool.
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Co-authored-by: Martin Holst Swende <martin@swende.se>
* all: move main transaction pool into a subpool
* go.mod: remove superfluous updates
* core/txpool: review fixes, handle txs rejected by all subpools
* core/txpool: typos