Avoid leaking marker icons

...i/trunk/src/org/fortiss/tooling/base/ui/editpart/.ratings

...tiss/tooling/base/ui/editpart/ConnectionEditPartBase.java

...tiss/tooling/base/ui/editpart/PositionedEditPartBase.java

.../org/fortiss/tooling/base/ui/editpart/allocation/.ratings

...editpart/allocation/AllocationSubDiagramEditPartBase.java

...rg/fortiss/tooling/base/ui/utils/DecorationIconUtils.java

...trunk/src/org/fortiss/tooling/kernel/ui/internal/.ratings

...org/fortiss/tooling/kernel/ui/internal/MarkerService.java

...src/org/fortiss/tooling/kernel/ui/internal/views/.ratings

...tiss/tooling/kernel/ui/internal/views/MarkerViewPart.java

.../trunk/src/org/fortiss/tooling/kernel/ui/service/.ratings

...org/fortiss/tooling/kernel/ui/service/IMarkerService.java