Horizontal list group feature suggestion

Created by: sts-ryan-holton

I've been playing around the list group component recently in some projects. One thing I'd like to see in Bootstrap 4.2 is possibly to have a horizontal list group or the ability to make any of the list groups provided (https://getbootstrap.com/docs/4.1/components/list-group/#basic-example) horizontal by adding a class. Technically, I don't know if it would be too difficuilt to add. I was playing around in the inspector and changed two things:

.list-group {
    // originally flex column
    flex-direction: row;
}

.list-group-item {
    // originally margin-bottom
    margin-left: -1px;
}

By making these relevant changes, you'd get the following:

And if we remove the max-width from the documentation:

I was thinking we could have a modifier class to the list-group-* something like:

-horizontal -vertical

Thoughts?