Fixes 357 duplicate axioms saving in OWL functional syntax.

The object renderer was not skipping already written out axioms
properly.

Added the ability to write declarations first, so all declarations
appear before the entities are used.
Change logging of remaining triples to use less memory.
Removed IRI.toString() call when checking blank nodes.

Profiling says that was taking up to 15% of parsing time.
Check can be done without turning the IRI in a string.