Add sort rrule

Author: andrewrosemberg

src/rulesets/Base/nondiff.jl

@@ -351,7 +351,10 @@ end
 @non_differentiable size(::Any, ::Any)
 @non_differentiable sizeof(::Any)
 @non_differentiable sleep(::Any)
+@non_differentiable sort(::AbstractVector)
+@non_differentiable sort!(::AbstractVector)
 @non_differentiable sortperm(::AbstractArray{Any})
+@non_differentiable sortperm!(AbstractVector{<:Integer}, ::AbstractVector)
 @non_differentiable split(::AbstractString)
 @non_differentiable split(::AbstractString, ::AbstractChar)
 @non_differentiable splitdir(::AbstractString)