Created by: tagliala
Hi,
I know this is a quite invasive PR and is highly opinionated.
I've noticed some inconsistent styling in the sources.
The use of empty line between blocks was quite inconsistent, this linter will increase the uniformity of the code.
Examples:
*-child
selectors https://github.com/twbs/bootstrap/blob/v4-dev/scss/_card.scss#L50 https://github.com/twbs/bootstrap/blob/v4-dev/scss/_card.scss#L236
::before
and ::after
selectors https://github.com/twbs/bootstrap/blob/v4-dev/scss/_popover.scss#L39 https://github.com/twbs/bootstrap/blob/v4-dev/scss/_popover.scss#L168
-left
and -right
variants https://github.com/twbs/bootstrap/blob/v4-dev/scss/_dropdown.scss#L124 while navbar hasn't https://github.com/twbs/bootstrap/blob/v4-dev/scss/_navbar.scss#L112