Big change: use RDF reification in Doyle TMS.

* [DOYLE,NEW] Added doyle_add_node/3 variant using RDF reification. This directly related TMS nodes to the RDF terms that construe an RDF triple.
* [RDF_MAT,NEW] Added option for adding multiple justifications per node. Entailment regime is also an option now.
* [RDF_REIFICATION,EXT] Allow a statement IRI to be given (a new blank node is still created in case the statement prameter is not instantiated).
* [TMS,NEW] Added tms_justification/4, used when checking for existing justifications in module RDF_MAT.