SYSML2_ — Replace Generic mapping classes by Initializers

The coexistence of both the "GenericTo*_Mapping" classes and the Initializer classes generates a significant number of redundancies in the model, and make it harder to understand and to maintain.

More specifically it makes the management of redefinitions much more complex with a very negative impact on the clarity of the specification.

In order to fix that, all the GenericTo*_Mapping classes shall be removed and replaced par their Initializer class equivalent in an appropriate way.

Replace classes as requested

In order to limit the impact on the current model, it is proposed to change the classes named GenericTo<metaclass_name>_Mapping rather than to replace them with existing Initializer classes that are actually used by Factory classes only.