removed useless code from principal_cuvature
removed useless code from principal_cuvature

aaronzou/Shape-Deformation,JianpingCAI/libigl,JianpingCAI/libigl,aaronzou/Shape-Deformation,JianpingCAI/libigl,aaronzou/Shape-Deformation,JianpingCAI/libigl,JianpingCAI/libigl,aaronzou/Shape-Deformation,JianpingCAI/libigl,aaronzou/Shape-Deformation