Fixed assignment operators for SacModelCone and SacModelCylinder.

[stefanbuettner]

Consider the following code:

// all the other fields of anotherSacCylinderPtr are set appropriately
anotheSacCylinderPtr->setInputNormals(someCloudContainingNormals);
typedef pcl::SampleConsensusModelCylinder<pcl::PointXYZ, pcl::Normal> SacCylinder;
SacCylinder::Ptr b(new SacCylinder);
*b = *anotherSacCylinderPtr;

then using b just like that in a SacMethod yields the error that no input point cloud having normal information was given.
Same goes for the cone model.

Cheers,
Stefan

[taketwo]

Thanks!