[TMVA experimental] Add correct RTensor interface for const objects
[TMVA experimental] Add correct RTensor interface for const objects

root-mirror/root,karies/root,root-mirror/root,root-mirror/root,karies/root,root-mirror/root,root-mirror/root,olifre/root,olifre/root,olifre/root,root-mirror/root,olifre/root,karies/root,karies/root,karies/root,root-mirror/root,karies/root,olifre/root,root-mirror/root,karies/root,root-mirror/root,olifre/root,olifre/root,karies/root,karies/root,karies/root,karies/root,root-mirror/root,olifre/root,olifre/root,root-mirror/root,olifre/root,olifre/root