check for c++0x unordered_map/set; add to capabilities
add some defines for checking what type of map is used
add MapCompare + #defines so map works when using std::map
handle REALSXP->STRSXP NaN case explicitly
cleanup table.h
pedantic fixes for REALSXP -> STRSXP conversion (matches R)
clean up table.h
add unit tests
update NEWS
fix some header comments
use MapCompare for sorting
always use mapcompare.h
initialization order; set seed explicitly as R's table might place NA, NaN in diff order
stop trying to be clever and just be portable
static unsigned long NA_REAL, R_NaN
explicitly convert occurrences of "-0" to "0"
add name to copyright header on modified files
merge Dirk's Rcpp changes; also add missing "return *this" in RObject_impl::operator=
Merge pull request #87 from kevinushey/master

Merging pull request #87 by Kevin with fixes to sugar table