(49g 50g) Theoretical Earth gravity g = g(latitude, height), WGS84, GRS80/67

[Gil]

Abandoned everywhere the closed notation for g calculation by Li and Götze in favor of more commun and clearer notation by Heiskanen and Moritz.

Changed the name CLOSED form, as what was calculated by Li and Götze when at height h above ellipsoid — with then abs(lat)≠90 or 0 — was not the normal g component, but guFR(EE).

For completeness, added, beside FREE variable guFR, the gbetaFR component, following the terminology of Heiskanen and Moritz.

The Maxima string (one huge set/string of instructions in HP) for checking — with the high digits precision — in MAXIMA free software the results was adapted consequently.