makes SparseView a true sparse expression and fix use of nesting types
makes SparseView a true sparse expression and fix use of nesting types

toastedcrumpets/eigen,TSC21/Eigen,TSC21/Eigen,Zefz/eigen,toastedcrumpets/eigen,toastedcrumpets/eigen,ROCmSoftwarePlatform/hipeigen,ritsu1228/eigen,pasuka/eigen,Zefz/eigen,pasuka/eigen,Zefz/eigen,TSC21/Eigen,ritsu1228/eigen,ROCmSoftwarePlatform/hipeigen,pasuka/eigen,toastedcrumpets/eigen,TSC21/Eigen,ritsu1228/eigen,Zefz/eigen,pasuka/eigen,ROCmSoftwarePlatform/hipeigen,ROCmSoftwarePlatform/hipeigen,ritsu1228/eigen,ritsu1228/eigen,pasuka/eigen