identical() now looks at the S4 bit

git-svn-id: https://svn.r-project.org/R/trunk@66620 00db46b3-68df-0310-9c12-caf00c1e9a41
Moved Rtanpi declaration to arithmetic.h.


git-svn-id: https://svn.r-project.org/R/trunk@66621 00db46b3-68df-0310-9c12-caf00c1e9a41
attributes<-() and class<-() now copy the S4 bit

git-svn-id: https://svn.r-project.org/R/trunk@66622 00db46b3-68df-0310-9c12-caf00c1e9a41
clarifications

git-svn-id: https://svn.r-project.org/R/trunk@66623 00db46b3-68df-0310-9c12-caf00c1e9a41
Include Rfe.exe in builds to give another workaround for PR#15981; still need to modify the installer to put it in place when appropriate.

git-svn-id: https://svn.r-project.org/R/trunk@66625 00db46b3-68df-0310-9c12-caf00c1e9a41
revert/postpone (the hot part of) -r66622

git-svn-id: https://svn.r-project.org/R/trunk@66626 00db46b3-68df-0310-9c12-caf00c1e9a41