Ordinal terminology change: dense -> contiguous
Minor refinement of is_range.
Introduced storage ref, non-owning wrapper for storage, useful for implementation of tensor views.
Minox changes in Tensor to allow it to work with StorageRef and implement TensorView (see test.C).
Added tests for StorageRef, and a simple implementation of TensorView.
Merge pull request #14 from evaleev/master

pull StorageRef (and TensorView) changes from evaleev/BTAS