Overhauling the notion of output range

[dsimcha]

== Quote from Andrei Alexandrescu (SeeWebsiteForEmail at erdani.org)'s article
> On 07/12/2010 01:31 PM, dsimcha wrote:
> > But efficiency only matters some of the time, assuming the kind of inefficiency in
> > question is small constant term inefficiency (as is the case here) and not O(N!)
> > inefficiency or 1000-fold constant term inefficiency.
> Historically the constant was large.

I'm not saying don't encourage the use of delegates that take ranges where it
makes sense, such as for formatting text.  I'm just saying support both and don't
force their use even where it doesn't matter.