Add rule: at-rule-no-unknown

[ghost]

Addresses #86 by adding a "new" rule extending stylelint's at-rule-no-unknown with a built-in list of exceptions including at-rules supported by Sass/SCSS.

[kristerkari]

Thanks! I'll try to review this as soon as possible

[kristerkari]

I had a look and this seems to add the missing things from @dryoma's pull request.

Would it be possible for you to add the README and CHANGELOG changes from #92? You can simply add a section called HEAD to the change log. I can then merge this and release a new version.

Thanks a lot for your contribution @lithiumlron!

[ghost]

@kristerkari I've added the changes. Hopefully everything is there.

[kristerkari]

Thanks! Looks good now.

I'm going to cut merge and then release a new version (might not have today since I need to leave soon, but if not then tomorrow).

[kristerkari]

Released as 1.5.0 https://github.com/kristerkari/stylelint-scss/releases/tag/1.5.0 🎉