Range of chars (narrow string ranges)

[Martin Nowak via Digitalmars-d]

Just want to make this a bit more visible.
https://github.com/D-Programming-Language/phobos/pull/3206#issuecomment-95681812

We just added entabber to std.phobos, and AFAIK, it's the first range
algorithm that transforms narrow strings to a range of chars, instead of
decoding the original string and returning a range of dchars.

Most of phobos can't handle such ranges like strings and you'd have to
decode them using byDchar to work with them.