We should also special case Java types, e.g., an interface. For instance, when asking the type hierarchy of [ISourceViewerEditor](https://github.com/scala-ide/scala-ide/blob/master/org.scala-ide.sdt.core/src/scala/tools/eclipse/ISourceViewerEditor.scala#L8), ``ITextEditor`` is returned as a super trait, while it should be an interface. It should be easy to add an additional ``Interface`` type and then display the Java Interface image in this case.