[R-SIG-Win] New Rtools sent to CRAN

[Duncan Murdoch]

I have just uploaded a new build of the Rtools33.exe installer to CRAN.  
It should appear on the mirrors within a day or two.

This installer includes the current build of gcc 4.9.3 from 
http://www.stat.ucla.edu/~jeroen/mingw-w64. It also includes
Jeroen's build of libicu55, which is necessary to build R.

The current R-devel build on CRAN should have the necessary changes to 
build R using this toolchain, but the default is still the previous gcc 
4.6.3 toolchain; users should follow the instructions on 
https://github.com/rwinlib/r-base#readme to set up their systems to use it.

Please post any problems here or to me or Jeroen, as appropriate. We're 
hoping to be able to use this toolchain in R 3.3.x.

Duncan Murdoch