Mathias LANG

From my experience, some experienced users really care about having `dub.selections.json` checked in, so that tests don't randomly break, so I think for the time being we should hold off...

> There's an unexpected (at least for me) amount of adjustments to configy in the second commit There's actually 3 adjustments in that commit: - Improve support for `Converter`: Previously...

> Interesting. Does this mean support for package.yaml files in the future? It would be at most 10 lines of code to do so, but that is not on the...

> Aside question: can configy be used to generate both CLI `--help` text and html documentation? CLI: No. Configy is not an argument parsing library, just a config parsing one....

Note that this is a draft for multiple reasons: - Gauge interest. Personally I think this would be wonderful to have, but I've felt that way about other features in...

> I am solidly against adding external dependencies to dub. If we vendor dependencies (like I did with configy itself), that problem is gone, isn't it ?

> Only if it is in this repository. That's what I meant by vendoring. But I think that's distracting from the aim of this PR: Do we want to move...

Right, d-yaml is not `-dip1000` compatible...

``` source/dyaml/constructor.d(484): Error: `@safe` function `dyaml.constructor.constructOrderedMap` cannot call `@system` function `std.container.rbtree.redBlackTree!(Node).redBlackTree` /usr/include/dmd/phobos/std/container/rbtree.d(1978): `std.container.rbtree.redBlackTree!(Node).redBlackTree` is declared here source/dyaml/constructor.d(490): Error: `@safe` function `dyaml.constructor.constructOrderedMap` cannot call `@system` function `std.container.rbtree.RedBlackTree!(Node, "a < b", false).RedBlackTree.stableInsert!(Node).stableInsert`...

@WebFreak001 : I've added a little unittest to show what errors look like. Obviously not the final form for testing, but it demonstrate our ability to easily check error messages...