* Improved Structures.png (better shading and color gradients, improved texturing details of the water). * Added HeightStructure to HeightStructuresFailureMechanism created with 'add demo traject' button. * TreeNodeInfo implemented for HeightStructure instance. Related to Issue [WTI-582] git-svn-id: https://repos.deltares.nl/repos/WettelijkToetsInstrumentarium/trunk@5622 5a3db67b-de53-47b5-99c8-a1c30a6650e2