reaction ruleml examples - key/keyref values

[greenTara]

The technical definition of CURIE allows a "no prefix" CURIE. However, most implementations (e.g. RDFa) avoid them. The CURIE for a default prefix reference would be
key=":r1"
not
key="r1"

as appears in https://github.com/RuleML/reaction-ruleml/blob/master/exa/dr/DistributedDerivationRuleImplementation.rrml

also should not be
key="#r1"

as appears in https://github.com/RuleML/reaction-ruleml/blob/master/exa/dr/FullDerivationRule.rrml
because that is not an absolute IRI or CURIE

Unfortunately, the "official" definition of the CURIE datatype does not filter out these constructions. Perhaps we should use a custom-built datatype that excludes these possibilities.

Also see http://wiki.ruleml.org/index.php/Priv:Reaction_RuleML_Github_Issues and http://wiki.ruleml.org/index.php/Key_and_Keyref_Content_Model