Support exact_version

[Hakuyume]

pkg-config provides name = version syntax to specify the exact version. It would be nice to add a wrapper for this functionality. Although pkg_config::probe_library("name = version") works, I think it is abuse.

[sdroege]

What API do you suggest for this? Something like Config::atleast_version(), a Config::exact_version()?

[sdroege]

Would in any case be easy to add, as well as a name >= version_min, name < version_max kind of check

[Hakuyume]

I was thinking Config::exact_version(). Taking (min, max) is also ok.

[sdroege]

I was thinking of both. Do you want to try your luck adding this? Otherwise I'll add it somewhere on my list but it might take a while until I get to it

[Hakuyume]

OK, I'll try.

[sdroege]

Awesome! If you get stuck somewhere and need help, feel free to ask here, or if you want me to take over :)

[Hakuyume]

@sdroege I made a PR (#75). Could you review it?