- More "natural" expression of NH free-surface term (case selectNHfreeSurf=1):   was: tmpSurf/(1+tmpSurf); changed to: 1/(1+Gamma) with Gamma=1/tmpSurf.
- More "natural" expression of NH free-surface term (case selectNHfreeSurf=1):
  was: tmpSurf/(1+tmpSurf); changed to: 1/(1+Gamma) with Gamma=1/tmpSurf.

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