ReSpec updated to fix biblio refs, and representation for literals

I have updated the version of ReSpec at ndjc.github.io to fix two issues:

Bibliography / references were not working - not reported as OASIS issue - fixed by switching to W3 biblio site

Representation of literals shown as Either - OASIS issue 51 - fixed, literals now show representation as "N/A"

Let me know if you see any problems.

Nick.