evm -x: MCOPY

[wjmelements]

Implements eip 5656 (MCOPY) for evm execution (-x)

Changes

• Add MCOPY
• Add test

[wjmelements]

This change caused two regressions on linux, apparently from undefined behavior. Not seeing any issue on macos.

I see errors for:

• tst/bin/evm
• tst/string.json