Used state inspector

[bertmiller]

In rbuilder there is an EVM inspector that is used to derive the reads/writes of a given order. In turn, this can be used for analysis of the transaction and inform block building - most notably to parallelize the building of a block by separating out potentially conflicting transactions.

It would be nice to get this functionality in rblib because eventually we will want the same kinds of features. However, I was not sure exactly where this functionality should live. You need to add the inspector when an instance of the EVM is being created, and there was no obvious (to me) way to make a modular refactoring that would allow for arbitrary inspectors to be supported.

On the other hand, this is the only use case for inspectors in block building that I know of, and the overhead of adding it is low (I think) so perhaps we just add it to rblib by default and don't make it programmable.

Thoughts?

[julio4]

Agree that it makes sense especially for potential parallelization execution later on. I would go with adding state trace inspector by default for now, and extend inspector modularity later if needed.

[bertmiller]

@karim-agha do you agree?