Used the newly created *AnyNonDistinct* to check whether all closing situations are the same. Removed IllustrationPointControlItemHelper.cs (now obsolete). The alternative was to have two (additional) helper classes to validate that their list of Closing situations is unique. Discussed with [~lubbers] Changed API of TopLevelFaultTreeIllustrationPointProperties from list of closing situations to boolean Related to Issue [WTI-1312] git-svn-id: https://repos.deltares.nl/repos/WettelijkToetsInstrumentarium/trunk@11934 5a3db67b-de53-47b5-99c8-a1c30a6650e2