Vote on region allocator

[dsimcha]

BTW, since the latest revision didn't get much review, I recommend we allow
"conditional yes" votes.  If you find some small issue that you think really needs
fixing, I think it's perfectly reasonable to say something like "yes, but please
fix X.".

== Quote from Jonathan M Davis (jmdavisProg at gmx.com)'s article
> Okay, David Simcha wrote some modules intended to form the basis for custom
> allocators in D, and that code has been reviewed in the "Formal Review of
> region allacator begins" thread. The review period has passed, and it's time
> to vote on whether we want to include it in Phobos as-is or not.
> Code:
> https://github.com/dsimcha/TempAlloc/tree/master/std/allocators
> Docs:
> http://cis.jhu.edu/~dsimcha/d/phobos/std_allocators_allocator.html
> http://cis.jhu.edu/~dsimcha/d/phobos/std_allocators_gc.html
> http://cis.jhu.edu/~dsimcha/d/phobos/std_allocators_region.html
> A yes vote means that we will be creating a new std.allocators module in
> Phobos and adding dsimcha's allocater, gc, and region modules to it (which
> provide the general custom allocator stuff, a custom allocator using the GC,
> and a custom allocator using a segmented stack respectively).
> A no vote means that we will not be including them at this time, and they will
> need to go through further revision and review if they are ever to be
> included.
> Please refrain from discussions in this thread. This thread is intended for
> voting only. Anyone can vote.
> The voting will last for approximately one week and will end on Saturday,
> October 1st at midnight in UTC (2011-10-01T00:00:00Z).
> - Jonathan M Davis