-atmospheric refraction integrated in rugged

src/main/java/org/orekit/rugged/api/Rugged.java

src/main/java/org/orekit/rugged/api/RuggedBuilder.java

src/main/java/org/orekit/rugged/errors/Dump.java

src/main/java/org/orekit/rugged/errors/DumpManager.java

...a/org/orekit/rugged/refraction/AtmosphericRefraction.java

...org/orekit/rugged/refraction/ConstantRefractionLayer.java

...in/java/org/orekit/rugged/refraction/MultiLayerModel.java

...ava/org/orekit/rugged/refraction/MultiLayerModelTest.java