The (unexported) bib() function supplied the location of the Rcpp.bib file for use by other vignettes (I have at least two other packages using it). However, this did not always work ... because the vignettes/ directory does not get processes right when you install from source. So now we put it in bib/Rcpp.bib and all is good.
This just changes the location, updates the accessor, adds a unit test we can now run, and updates the link in the vignettes.
Should be low key. Review of course still appreciated.
moved bibtext file to be always accessible
location in vignettes meant installation from source made it unavailable
additional unit test
test the bib() function