Incorporated comment tester: - Added conversion from double to ReadWaveConditionsInputStepSize -- Added extensionmethod in XElementExtensions: retrieve double and convert it to desired type with a type converter -- Added tests to verify conversion - Adjusted for the CalculationConfigurationReader Related to Issue [WTI-1158] git-svn-id: https://repos.deltares.nl/repos/WettelijkToetsInstrumentarium/trunk@8971 5a3db67b-de53-47b5-99c8-a1c30a6650e2