Moved StochasticSoilModelImporter to IO namespace. Added IStochasticSoilModelChangeHandler to inquire user for change confirmation. Implemented TestStochasticSoilModelChangeHandler utility class to use in testing. Added Ringtoets.Piping.IO.TestUtil to house the utility class. Implemented StochasticSoilModelChangeHandler with a basic implementation. Extracted TestStochasticSoilModelUpdateModelStrategy from StochasticSoilModelImporterTest. Related to Issue [WTI-1093] git-svn-id: https://repos.deltares.nl/repos/WettelijkToetsInstrumentarium/trunk@8091 5a3db67b-de53-47b5-99c8-a1c30a6650e2