Added restriction to fraction parameter in GetInterpolatedPointAtFraction so that extrapolation is not possible anymore. Corrected persistence of the UpliftCriticalSafetyFactor. Related to Issue [WTI-765] git-svn-id: https://repos.deltares.nl/repos/WettelijkToetsInstrumentarium/trunk@4625 5a3db67b-de53-47b5-99c8-a1c30a6650e2