Migrate roughly half of the base components into base
Adds a target for easily formatting CSS
Further CSS amends/migration (#5921)
1. tooltips within tables where a slightly bit troublesome due to a mix
of `inline-flex`, `overflow` and the need for truncation. This refineds
tooltips a slight bit more to work 'everywhere'.
2. We also move tooltip to use the correct color and min-width from
structure, but we overwrite the min-width here until we get confirmation
on widths/alignment of text within a tooltip.
3. Tiny fixes for breadcrumbs and toggle-buttons in tabular listings
4. Now we inline-flex our table cells, it means it is impossible to
truncate text without wrapping it in another element. This wraps all
Description like text in `<p>` tags. Generally the first column of text
is already wrapped in an `<a>` tag. Other items such as consul tags and
policy names etc get 'cutoff' rather than truncated.
5. We are now using all the icons from `@hashicorp/structure-icons`
* Begin refactoring CSS into component folders. Moved most
components into layout/skin folders, left out a couple of ones I want
to think about more.
* Adjust grays based on recent Structure changes
* Switch to fullscreen layout for lists and detail, left aligned forms (#4435)
* Specifically use the 'actions_close' label, not just the :last-child (actions-group)
* Replace some non-var-ed colours in vaults code skin, plus prefixing (black and white)
