prepare to merge mutual methods from Refining and InterRefining

...it/rugged/refining/generators/GroundMeasureGenerator.java

...kit/rugged/refining/generators/InterMeasureGenerator.java

...g/orekit/rugged/refining/models/PleiadesViewingModel.java

src/tutorials/java/AffinagePleiades/GroundRefining.java

src/tutorials/java/AffinagePleiades/InterRefining.java