deprecate IntegralInvariant{Gaussian/Mean/NormalVector}Estimator, and modifying testIntegralInvarientEstimator2D to use the new one
resolving conflict with deprecated classes
adding some 3D II functors (k1, k2, K) in IIGeometricFunctors
oups ... '*=' instead of '*'
Modification in testIntegralInvariantGaussianEstimator3D in order to use IntegralInvariantCovarianceEstimator + IIGaussianCurvature3DFunctor
Modification in testIntegralInvariantMeanEstimator3D in order to use IntegralInvariantVolumeEstimator + IIMeanCurvature3DFunctor
Modification in exampleIntegralInvariantMeanEstimator2D/3D in order to use IntegralInvariantVolumeEstimator + IIMeanCurvature2D/3DFunctor
minor edit
removing some warnings in DGtal