Remove scaling of net electric to allow negative net electric

[timothy-nunn]

Description

Remove the scaling of net electric as negative net electric is physically meaningful

Checklist

I confirm that I have completed the following checks:

• I have justified any large differences in the regression tests caused by this pull request in the comments.
• I have added new tests where appropriate for the changes I have made.
• If I have had to change any existing unit or integration tests, I have justified this change in the pull request comments.
• If I have made documentation changes, I have checked they render correctly.
• I have added documentation for my change, if appropriate.

[mkovari]

Note the the same scaling is still done in ife.f90:

      !  Scaling to prevent negative pnetelmw
      if ( (pnetelmw < 1.0D0).and.(ipnet == 0) ) then
        pnetelmw = 1.0D0 / ( 1.0D0 + abs(pnetelmw-1.0D0))
      end if