Removed the function
yy_fatal_error which even though it was never
actually called, triggered some R CMD check nuisance
Removed useless dependency on Rcpp which bibtex no longer uses
Added cite by key functionality to
read.bib, pull request by
Fix for bib files with no content.
write.bib contributed by Renaud Gaujoux.
% in error reporting in read.bib.
Fix provided by Renaud Gaujoux.
Fixed long standing bug re backslahes.