* Removed unit tests that are already covered by more complex unit test. * Extended StabilityPointStructuresContext with parent failuremechanism. * Implemented context menu items to delete StabilityPointStructure instances. Related to Issue [WTI-966] git-svn-id: https://repos.deltares.nl/repos/WettelijkToetsInstrumentarium/trunk@6623 5a3db67b-de53-47b5-99c8-a1c30a6650e2