Generate series of `.table-responsive-*` classes to accomodate overflowing tables in a variety of screen sizes

Rename `.table-inverse`, `.thead-inverse`, `.thead-default` to `.table-dark`, `.thead-dark`, `.thead-light` respectively

(#22414) Rename variables `$table-inverse-bg`, `$table-inverse-accent-bg`, `$table-inverse-hover-bg`, `$table-inverse-border-color`, `$table-inverse-color` to `$table-dark-bg`, `$table-dark-accent-bg`, `$table-dark-hover-bg`, `$table-dark-border-color`, `$table-dark-color` for consistency

1. Instead of having two selectors, we use the `.list-group-item` class and have coverage for list items and anchors.
2. Rather than override all border values, we only override what we set with `border-top`.

I never use this dang list and it just falls out of date far too easily. Dropping for my own sanity.

Fixes #23360 by restoring just the offset class generation to our grid
framework mixins. Also restores the `make-col-offset` mixin.

Docs have been restored to illustrate this behavior and merged with the
newer margin utilities examples.

I suggest removing `color: #FFF` from the `badge` class, because it is
provided by the `badge-<modifier>` classes along with a
background-color, whereas there is no corresponding background-color
provided on the `badge` class itself.

Background
----------

According to the documentation:

> [badge] Requires one of the contextual, color modifier classes for `color` and
> `background-color`.

That is, color and background color should be provided by a modifier
class, rather than the badge class itself.

e.g. `<span class='badge badge-primary'>4</span>`

In general, providing a `color` property without also providing a
`background-color` should be avoided. [W3 QA tips]

In this context, this is a problem only if someone creates a `badge`
without providing a modifier. Such an omition may be difficult to trouble-shoot,
because this will most likely yield white text on a white background.

[W3 QA tips](https://www.w3.org/QA/Tips/color)

Uses some if/else action to ensure there's readable text on hover. Swapped out a hex value to a variable while I was in there.

Fixes #23398, fixes #23351.

Fixes #23397

* Remove remaining references to v4 Alpha

This commit removes the remaining refrences to the v4 Alpha website and replaces them with the
corresponding v4 Beta ones.

**Note:** We have to hard code the current docs version at some places. Wouldn't it be good to have a `/docs/latest/` redirect to solve this "issue" in the future?

* Don't update the domain in the CNAME file

There is no _custom.scss file anymore.

* use a mixin there
* revamp .btn-link to match default and outline variants
* remove unnecessary properties

move max-width: 100% on .container to the root of the make-container mixin so it's not repeated at compilation (#22947)

Apply `align-items: center;` to `.input-group` instead of input group sub components, causes `.input-group .form-control` and `.input-group-addon` to be large when next to a tall element

* Fix to Chrome inheritance bug (#22872)

* Remove box-sizing from html

box-sizing removed from html and order of wild card selected and html selector swapped to maintain correctness of comments.

Custom File `$custom-file-focus-box-shadow` should show even if box shadows are disabled

Custom File variables should inherit from inputs

* add margin variable for breadcrumb

* add margin variable for breadcrumb correction

* breadcrumb margin variable changes after review

* reduce # of spacing rules by combining x & y with t r b l

* Remove unnecessary spaces