MOF24 — Fix resolution to issue 15398 from MOF2.4 ballot 2

MOF::Reflection must merge UML::Classes::Kernel instead of importing it because it defines MOF::Reflection::Element as an increment of UML::Classes::Kernel::Element
MOF::Identifiers does not need to import PrimitiveTypes since MOF::Common already does and that non-conflicting visible elements are imported transitively
MOF::Extension needs to import UML::Classes::Kernel, it does not need to import PrimitiveTypes since Kernel does this already via the merge of Core::Constructs, which imports PrimitiveTypes
MOF::CMOFReflection must merge MOF::Reflection because it uses MOF::Reflection::Object and also defines MOF::CMOFReflection::Element and MOF::CMOF::Reflection::Factory as increments of the classes in MOF::Reflection

Apply the changes to the MOF2.4 metamodel as described in the summary.
Additionally:

• MOF::Reflection must import MOF::Common since operations defined in MOF::Reflection depend on types defined in MOF::Common
• MOF::CMOFReflection does not need to import MOF::Common since it merges MOF::Reflection, which imports MOF::Common
• MOF::CMOF does not need to merge UML::Classes::Kernel per resolution 15398 because MOF::CMOF merges MOF::CMOFReflection, which merges MOF::Reflection, which merges UML::Classes::Kernel
• MOF::EMOF does not need to merge UML::Classes::Kernel per resolution 15398 because MOF::EMOF merges MOF::Reflection, which merges UML::Classes::Kernel