Moving the txpool transaction pull into the execution phase and looping
until the gas is used up or the txpool runs dry.
Removed the concept of local vs remote transactions as comments/code
showed this split was no longer in use.
Created a `PreparedTxs` collection to satisfy the use case in the
integration tool when mining is active.
Untested locally as I have no way of mining/validating currently.
Co-authored-by: Alex Sharov <AskAlexSharov@gmail.com>
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