Add btn-info to buttons examples

Remove outdated btn-xs and btn-group-xs

Fix #17234

v4 - Fix broken holder.min.js link in album example

update broken holder.min.js link

Card variables should be in _variables.scss

v4 - Use doge instead of css for <pre> example

v4 - Add pixel values for the rem breakpoints and column sizes

rm docs references to nuked stateful button feature

v4 - Add new table variants not in V3 to What's new

v4 - Fix Broken link in text alignment section of v4 Card docs

v4 - Fix broken link in Sass mixins section of v4 docs

v4 - Use border-radius mixin in form-control-sm and form-control-lg

v4 - Add new table functionality to table migration section

v4 - Remove weird extra border from GitHub follow buttons on v4 Team page

Fix #17175

X-Ref Original Against Wrong Branch: #17179

Calls out the new `.table-inverse`, `.table-reflow`, `.thead-default` and `.thead-inverse`

Audit the new table variants in V4 that aren't in V3

Fix #17177

Simplest example is using horizontal variants using rows.

Fix #17182