Phobos addition formal review: std.experimental.allocator

[HaraldZealot via Digitalmars-d]

>
> So we have:
>
> * 1 request to change names;
> * 3 requests to wank around the directory structure;
> * 0 of everything else.
>
> Sigh.
>
>
> Andrei

Yesterday I have found an error in documentation and have left a 
comment about it on github PR.

And I only start to read the documentation, so I think there will 
be plenty small things to polish.