* Adding --no-color flag to sass stylelint
* Adding --no-color to all stylelint args
* Adding --no-color expectation to stylelint tests
* Properly handling SyntaxError for stylelint; adding corresponding test
* Fixing CSS stylelint parameters and adding regression test
Ale saves a temporary file (%t) which does not share the same path as
the original file, breaking import statements with relative URLs.
This fix sends content to `lessc` over stdin and adds
the current file (%s) as one of the included paths, so statements like
`@import '../utils' will correctly resolve based on the current file path.
