N-Triples and N-Quads ready for review

All ISSUES in the FPWD of both N-Triples and N-Quads are resolved. The
comment on N-Triples (originally a comment on Turtle) is also addressed by
the introduction of "A canonical N-Triple document" in the conformance
section.

N-Triples:
https://dvcs.w3.org/hg/rdf/raw-file/default/rdf-turtle/n-triples.html
N-Quads: https://dvcs.w3.org/hg/rdf/raw-file/default/nquads/index.html

Cheers,
Gavin