Use atsign-simd for sum
fix bug in sum_kbn on empty input
remove hash call on our hash, so we have a better guarantee of serializer uniqueness
Use asymmetric up/down behavior in history_move_prefix.
allow using a non-returning cfunction as a void function. fixes #8484
Merge pull request #8486 from blakejohnson/asymmetric-up-down

Use asymmetric up/down behavior in history_move_prefix.
Merge branch 'master' of github.com:JuliaLang/julia into jb/checked_int_trunc
Merge branch 'master' of github.com:JuliaLang/julia into sjk/simd-sum

Conflicts:
	base/reduce.jl
Merge pull request #6928 from JuliaLang/sjk/simd-sum

Use atsign-simd for sum
Merge branch 'master' of github.com:JuliaLang/julia into jb/checked_int_trunc

Conflicts:
	base/reduce.jl