Added ensure-datarange, and applied it in the right places.
Previously I had assumed that everything was a datatype, and this is not true.
Added *explicit* var, which forces use of "data-" or "object-" function
rather than their heuristic equivalents. Added support in all rendered forms.
Added earmuffs to *terminal-strategy*. A few more OWL types supported.
More tests added.
Update due to change in render.clj.
Add sio.owl as a test subject.
Add sio_header.clj which loads rendered form of sio.owl.