Changeset 7535

Merged changset [7339] from ORCHIDEE_2_2 into the trunk, see ticket #821 :

Contributes to ticket #416: field capacity and wilting point are now calculated in slowproc_soilt, instead of being defined in constantes_soil_var for each texture class. The latter values had been calculated with the same functions as in slowproc_soilt, but truncated, so the results are not perfectly preserved: on global scale average, FC is reduced by 0.005%, WP by 0.02%, and total ET by 0.02% (mean for 1 day = Jan 5th).