Help docs for median "checknan" keyword incorrect

[tinybike]

julia> help(median)
Base.median(v; checknan::Bool=true)

   Compute the median of a vector "v". If keyword argument
   "checknan" is true (the default), an error is raised for data
   containing NaN values. Note: Julia does not ignore "NaN" values
   in the computation. For applications requiring the handling of
   missing data, the "DataArray" package is recommended.

But, median actually returns NaN if the vector contains a NaN, rather than raising an error:

julia> x=[1,2,NaN];

julia> median(x)
NaN

[jiahao]

The docs haven't been updated since #6820.

[ivarne]

@simonster Can you have a look at this regarding a possible backport. I would like as much documentation update in 0.3.2 as possible, but I'm confused and think the code changes in e24fac0 looks like they maybe shouldn't be backported.

I can cherry pick only the documentation changes, but think it is better to ask than to just do it.