Stylelint: Not all instances of declaration-no-important are tripping the linter

[Tregonia]

Found that there are instances of !important in the base theme styles that are not tripping the linter.

https://github.com/mediacurrent/theme_generator_8/blob/master/generators/app/templates/_src/patterns/global/utils/_mixins.scss#L15

The linter issues can be resolved with the following ignore comment, but the reason for these items not tripping the linter needs to be isolated.
/* stylelint-disable-next-line declaration-no-important */

The clearfix mixin is also is not tripping the rule-empty-line-before rule.

All instances are found within mixins.