* Fixed some linting issues

* Run npm tasks after scss cleanup

* Revert "Run npm tasks after scss cleanup"

This reverts commit 1103a0da.

* Property sort order for grid

* Let's respest the property order in the mixins

* Respect property sort order in reboot file

* ::-ms-expand is a vendor-prefix, add it to the scss-lint disable

* Revert hover mixin comment

* Fixed missing mixin hover-focus

don't implement for the outline style because outline buttons get no shadow by default

- removes original outline removal (hah)
- replaces it with an explicit `outline: 0` on `.btn`
- instead of replicating `:hover` for `:focus`, uses custom and themed `box-shadow` for an "outline"
- not mapped to the `$enable-shadows` variable because accessibility

Trying to simplify our output here by revamping these selectors. We overcomplicated things by setting hover styles for nearly every state (disabled and active included), and we set them in the wrong order.

This commit does the following:

- Reorders states so disabled comes before active, thereby removing the need to set disabled-active styles.

- Removes all focus and hover styles from disabled states as those will naturally inherit from the default button state.

- Renamed `.open` to `.show` to fix dropdown toggle highlighting.

- Tweaked some indendation in the Sass.

Fixes #20609

PR #20641, another solution to this issue, hard-codes use of $body-color, which may not be the desired color for the text when hovering.

- Rename -height to -height-base to match other vars
- Drop use of -height across the board and rely on it to be inherited
- Adjust padding of .dropdown-header to account for different line-height of h6 heading element (this needs refactoring for variables and rems also)

[skip sauce]
[skip validator]

If we want to support namespaced import:

```scss
.twbs {
  @import 'bootstrap';
}
```

We cannot use `selector &`, see sass/sass#1817.

`fieldset[disabled] &` is not needed as we no longer support IE8.

- no real need for everything to be 100% shared
- padding looked and felt too large for inputs but not for buttons
- tying forms and buttons seems fine, but throwing in pagination feels wrong

:disabled is supported in IE9+ and all modern browsers