Check for signedness of char when performing key conversion in CUDA's radix sort.
Merge pull request #369 from thrust/fix-radix-sort-char

Check for signedness of char when performing key conversion in CUDA's ra...
Merge pull request #370 from thrust/1.7.0

Pull last minute change from 1.7.0
Avoid redefining __CUDA_ARCH__ in B40C code.
Introduce B40C_CUDA_ARCH to use instead.
Merge pull request #372 from jaredhoberock/cuda_arch

Avoid redefining __CUDA_ARCH__ in B40C code.
Merge branch 'master' of github.com:thrust/thrust into merge_sort