Started doxygen-based documentation:
0) BTAS code and TWG spec need to be distinguished
1) outlined Range concept
2) added synopsi for Range and Tensor classes
Slight refinement of the interpretation of Range::iterator type.
Make serialization non-intrusive so that it’s clear that non-Boost serialization can be tacked on too.
Currently can use btas::tensor as a tile in TiledArray::Array, but only initialization works.
Demonstrates that using current btas::tensor directly is not possible. TA::Array tries to construct tensor using range and value.
Default Range for now is the TiledArray::Range.
What is storage? Sequential container + operator[]?
All tests, except dgemm compile; all but axpy run (axpy segfaults).
1) Introduced BoxRange concept
2) Implemented concept checks for Range and BoxRange
axpy and gemm use require BoxRange-based Tensor
Minor bugfix
Slight refinement of the Storage concept.
Updated TA test.
Refined BoxRange concept.
Introduced TWG.Tensor and TWG.BoxTensor concepts.
Range-related refinement of TWG specs and BTAS. Currently still using TA::Range, need to port it over.
Added adaptors to std::vector/std::array to make them behave similarly.
All tests now work.
Now can make fixed-size tensors based on std::array storage.
Merge branch 'master' of https://github.com/BTAS/BTAS into BTAS-master

Resolved Conflicts:
	btas/generic/axpy_impl.h
	btas/generic/gemm_impl.h
	btas/tensor.h
	btas/tensor_traits.h
	test/test.C