Move to individually versioned packages with Lerna (#254)

* New, responsive site based on individually versioned components with silly fast navigation, lazy loaded deps as docs are viewed
  * Basic accessible search with build-time index generation
* Update README for individual versioning, add legacy README with legacy usage
  * Add documentation for site updating and architecture
  * Add docs for documentation generation, link to docs, remove references to Precursors
  * Add instructions for adding/editing components
  * Add docs to show how to update DNA and icons
  * Add docs for getting DNA variables from @spectrum-css/vars
  * Document issues with npm ci and installing optional dependencies

* Update to DNA 5.18.1
* Update icons to 4.1.0
* Audit DNA status for all components
* Add nvmrc
* Export a experimental tree-shakable DNA variable object from @spectrum-css/vars

* Update Textarea line-height and min-height, closes #231
* Fix spinner buttons appearing on Steppers in Firefox, closes #214
* Fix search field on iOS, closes #229 
* Fix Menu chevron vertical alignment, fixes #240
* Fix horizontal alignment of labels in anchor buttons, fixes #239
* Remove button outline when focused in Firefox, fixes #161
* Fix bar loader label in IE 11, fixes #242
* Fix Radio label margins when labels are below, fixes #246
* Fix Checkbox icon color when checkbox imported before icons, fixes #219 (#235)
* Add Adobe Clean UX support, closes #189  (#248)
* Fix fallback fonts for ar, he, ja, zh-Hans, zh-Hant, and ko, closes #232 (#248)
* Removed float from tags, fixes #218 (#237)
* Make Slider grab handle look right in docs, closes #255
* Add missing Asset docs, closes #256
* Add Menu .is-highlighted so we can indicate highlight without mis-using .is-open, closes #258 
* Support using links as menu items, closes #257
* Fix incorrect height for small BarLoader, fixes #259

site/includes/dependencies.pug

@@ -6,12 +6,12 @@ link(rel='icon', type='image/png', href='favicon.png')
 link(rel='stylesheet', type='text/css', href='css/prisim/prism.css', data-prism)
 
 link(rel='stylesheet', type='text/css', href='../components/vars/spectrum-global.css')
-link(rel='stylesheet', type='text/css', href='../components/vars/spectrum-lightest-unique.css')
-link(rel='stylesheet', type='text/css', href='../components/vars/spectrum-light-unique.css')
-link(rel='stylesheet', type='text/css', href='../components/vars/spectrum-dark-unique.css')
-link(rel='stylesheet', type='text/css', href='../components/vars/spectrum-darkest-unique.css')
-link(rel='stylesheet', type='text/css', href='../components/vars/spectrum-medium-unique.css')
-link(rel='stylesheet', type='text/css', href='../components/vars/spectrum-large-unique.css')
+link(rel='stylesheet', type='text/css', href='../components/vars/spectrum-lightest.css')
+link(rel='stylesheet', type='text/css', href='../components/vars/spectrum-light.css')
+link(rel='stylesheet', type='text/css', href='../components/vars/spectrum-dark.css')
+link(rel='stylesheet', type='text/css', href='../components/vars/spectrum-darkest.css')
+link(rel='stylesheet', type='text/css', href='../components/vars/spectrum-medium.css')
+link(rel='stylesheet', type='text/css', href='../components/vars/spectrum-large.css')
 
 each dep in dependencyOrder.filter((dep) => dep != 'vars' )
   link(rel='stylesheet', type='text/css', href='../components/' + dep + '/index-vars.css', data-dependency=dep)