Reimplemented revision 12140 from trunk after fixing failed tests: - Added fix for migration: -- Insert a temporary calculation group row entry during the migration and update the foreign key of the MacroStabilityInwards related failure mechanism rows. This prevents the CalculationGroupReadExtension from throwing a NULL reference exception when it reads the root calculation group --- Added read and create extensions: - Expanded the calculation group -- Read and Create added to read or create the entities for macrostability inwards calculation (scenario) - Expanded asserts on the piping side: -- Removed .Value access in the tests => use .GetAccuracy instead of accessing the private variable of a RoundedDouble -- Added asserts on the output values when creating or reading piping (semiprobabilistic) output entities - Added entities to explicitly load in the PartialRingtoetsEntities