Issue #3265140 by Spokje, bnjmnm, lauriii, mstrelan, dww, Wim Leers, xjm, murilohp, daffie: Move QuickEditImageController from image to quickedit

Issue #2866818 by harsha012, BrightBold, brahmjeet789, joelpittet: Update stylelint rule number-leading-zero to be consistent with Drupal's CSS standards

Issue #2878548 by alexpott, droplet, Cottser, idebr, joelpittet, xjm, martin107: Fix CSS whitespace issues

Issue #2421427 by samuel.mortenson, droplet, dawehner, nod_, Cottser, Wim Leers, xjm, Gábor Hojtsy, Bojhan, tstoeckler, webchick, naveenvalecha, alexpott, LewisNyman, chris_h, Manjit.Singh, phenaproxima, avitslv, yoroy, tim.plunkett, Mixologic, ipwa, slashrsm: Improve the UX of Quick Editing single-valued image fields

Issue #2566771 by Cottser, mortendk, jstoller, LewisNyman, mdrummond, Gints Ērglis, sqndr, Chernous_dn, Manjit.Singh, axe312, emma.maria, davidhernandez, lauriii, jaxxed, akalata: [Voltron patch] Move all remaining *.theme.css to Classy

Issue #1649780 by effulgentsia, jibran, Wim Leers, nod_, hefox, joelpittet, kaare, BarisW, sun, rbayliss, Cottser, fubhy: Remove first/last/odd/even classes in favor of CSS3 pseudo selectors.

Issue #2015789 by fubhy, echoz, rteijeiro, LewisNyman, penyaskito: Remove language_css_alter() (RTL stylesheets) in favor of HTML 'dir' attribute.

Issue #1987066 by Kevin Morse, JohnAlbin, rteijeiro, echoz, ry5n: Rename files to match CSS file naming convention.