phobos dependencies

[Shammah Chancellor]

On 2013-12-18 22:19:14 +0000, H. S. Teoh said:

> I've been saying this over and over: now we have package.d, let's make
> use of it. Jonathan has been working on splitting up std.datetime
> (though that has yet to materialize); I think std.algorithm and
> std.range are due, too.

+1 on this.   When I have some time I was going to make a pull request 
on some of the modules.

-Shammah