Implement datastructure support in the pipelining framework.
Add datastructure section to documentation.
Update pipelining method matrix in the documentation.
Add pipelining datastructures unit tests.
Fix pipelining datastructures get_datastructure and set_datastructure methods.
Add pipelining datastructures example.
Replace ostream_writer with printf_ints in pipelining datastructures example.
Mention auxiliary datastructures example in the documentation.