This PR overhauls the .media component by reducing it to only two required classes, .media and .media-body. Everything else can be accomplished with utility classes for padding, margin, and alignment. This also overhauls the docs to improve copy, add more examples, and improve existing examples with the new markup and utils usage guidelines.
While working on this, I took a look at #20408 (closed). Turns out that's a known bug with inline flex items not being counted in IE10-11. I've added a docs warning for that.
As an aside, I'll likely be tackling some flex utils name changes and docs updates in a follow-up PR. We're missing some key flex utils and the class names could use a small change for consistency with our other property-value utils (e.g., d-flex).