Migration of packages under refining (generators, metrics, models) under

src/tutorials/java/RefiningPleiades/GroundRefining.java

src/tutorials/java/RefiningPleiades/InterRefining.java

src/tutorials/java/RefiningPleiades/Refining.java

...a/RefiningPleiades/generators/GroundMeasureGenerator.java

...va/RefiningPleiades/generators/InterMeasureGenerator.java

...utorials/java/RefiningPleiades/generators/Measurable.java

...utorials/java/RefiningPleiades/metrics/DistanceTools.java

...ls/java/RefiningPleiades/metrics/LocalisationMetrics.java

src/tutorials/java/RefiningPleiades/models/OrbitModel.java

...ls/java/RefiningPleiades/models/PleiadesViewingModel.java