std.experimental.allocator

[Andrei Alexandrescu via Digitalmars-d]

It's been bitrotting for a while, I've rebased and it has passed tests 
now. Who will do the honors?

https://github.com/D-Programming-Language/phobos/pull/3405

There are three pull requests open against my fork, I invite the authors 
to rebase them or retarget them against the phobos mainline after 3405 
is pulled.


Thanks,

Andrei