-RM-12-MR-[NavSlices] provide slice position properties for the Selection Manager
At the moment the NavSlices create and register their porteries for the three slice position in the WSelectionManager inside of the kernel. This may lead to uninitalized properties when other modules request the slice properties from the Selection Manager when NavSlices weren't initialized yet.. In order to give other modules the slice positions, the selection manager should create them before any module comes up, and all modules (including navslices) should ask the selection manager for the slice positions.
(from redmine: created on 2011-07-28, closed on 2011-08-18)