Add redundant writes to Hamt and Amt to interop

[austinabell]

Summary of changes
Changes introduced in this pull request:

• Couldn't not put this functionality behind a feature :)

Edit: I changed this to only use the feature in actors. I thought about it more and the only time the redundant writes is needed is within the VM execution (and excluding state tree reads/writes since those aren't charged) so this barrier can safely be set here I am almost certain.

The reason this will not cause any issues is because the feature changes what the (H)amt will functionally do and what is persisted, but the data will be the same and the root Cid will always match. The benefit to doing this way is we don't have to deal with the performance regression outside of VM where the blockstore reads/writes diff cannot cause a consensus issue.

Reference issue to close (if applicable)

Closes #729

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