Rework of whitelisting interfaces and mechanism (now supports hierarchical definition).

.../fortiss/tooling/kernel/ui/extension/ITutorialStepUI.java

...tiss/tooling/kernel/ui/extension/ITutorialUIProvider.java

...ing/kernel/ui/extension/ITutorialUIWhitelistProvider.java

...nel/ui/extension/base/TutorialUIBlacklistAllProvider.java

...nel/ui/extension/base/TutorialUIWhitelistAllProvider.java

...ooling/kernel/ui/extension/data/TutorialStepUIAtomic.java

...ortiss/tooling/kernel/ui/internal/ContextMenuService.java

...fortiss/tooling/kernel/ui/internal/TutorialUIService.java

...g/fortiss/tooling/kernel/extension/ITutorialProvider.java

...c/org/fortiss/tooling/kernel/extension/ITutorialStep.java

...iss/tooling/kernel/extension/data/TutorialAtomicStep.java

...rtiss/tooling/kernel/extension/data/TutorialStepBase.java

.../org/fortiss/tooling/kernel/internal/TutorialService.java