implements changes following Flo's review

org.fortiss.tooling.kernel.ui/trunk/plugin.xml

....tooling.kernel.ui/trunk/schema/constraintVerifierUI.exsd

...rg/fortiss/tooling/kernel/ui/extension/IConstraintUI.java

...s/tooling/kernel/ui/extension/base/ConstraintUIBases.java

...rtiss/tooling/kernel/ui/internal/ConstraintUIService.java

...s/tooling/kernel/ui/internal/ToolingKernelUIInternal.java

...internal/introspection/details/KISSDetailsUIRegistry.java

...ndler/ConstraintServiceIntrospectionDetailsUIHandler.java

...ler/ConstraintUIServiceIntrospectionDetailsUIHandler.java

...on/items/ConstraintUIServiceIntrospectionDetailsItem.java

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

...rtiss/tooling/kernel/ui/service/IConstraintUIService.java

...rg/fortiss/tooling/kernel/ui/util/ConstraintsUIUtils.java