Added md5, sha1, sha256, sha384, and sha512 functions.
Add Date functions, note that RDF::Litearl::DateTime cannot distinguish between a time with a timezone of GMT vs no timezone.
Update to use #tz and #timezone methods for Literal::DateTime
Added BNODE and IRI/URI functions.
As per note in COALESCE, In SPARQL, evaluating an unbound variable raises an error. This causes minor changes to #bound and #order.
Added if, coalesce, uuid and struuid functions.
Enable bind tests.
Create SSE construct_spec with bound/unbound query tests.
Separate ask and describe specs out from query_spec.
This addresses issue #8, but requies un-released changes to the rdf gem.