Checkstyle corrections (tabulations and unused import)

.../java/org/orekit/rugged/adjustment/AdjustmentContext.java

...t/rugged/adjustment/GroundOptimizationProblemBuilder.java

...ed/adjustment/InterSensorsOptimizationProblemBuilder.java

...ava/org/orekit/rugged/adjustment/LeastSquareAdjuster.java

.../orekit/rugged/adjustment/OptimizationProblemBuilder.java

...java/org/orekit/rugged/adjustment/measurements/Noise.java

...rg/orekit/rugged/adjustment/measurements/Observables.java

.../orekit/rugged/adjustment/measurements/SensorMapping.java

...rugged/adjustment/measurements/SensorToGroundMapping.java

...rugged/adjustment/measurements/SensorToSensorMapping.java

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