Sort behaves like R's 'sort(..., na.last=TRUE)'
Fix for NA handling in IndexHasher
See if Travis fails again since I can't reproduce locally
Need a specialized 'equals' to handle NA, NaN in Hasher
Some renaming / restructuring
Missed these files
Tidy up and use Rcpp_IsNA, Rcpp_IsNaN where possible
::Rcpp::traits::NAComparator -> NAComparator
Fix for Rcpp_IsNaN, given BDR's advice on R-devel
Unit tests and reshuffling for NA, NaN handling in Rcpp
Some reformatting, + a NEWS entry
Better motivation for current NA checking