Cleanup of NEMO files

[WallyMaier]

Proposed Changes

This is a chore PR to const variables when allowed and to alter loops to prevent declared iterators. This may be unnecessary/overkill.

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[pcarruscag]

Good stuff

[WallyMaier]

@jtneedels @pcarruscag Any idea why the regressions may be struggling?

[jtneedels]

@jtneedels @pcarruscag Any idea why the regressions may be struggling?

It's just axi_viscone, so something must have been changed in the axisymmetric source residual.

[pcarruscag]

You only see changes on residuals that are -20 so I think you are ok.
Taking those variables from members to local variables may allow the compiler to re-order some stuff for optimization.

[jtneedels]

LGTM!