git commit -m 'Issue #2377397 by Wim Leers, alexpott: Themes should use libraries, not individual stylesheets'
Issue #2350823 by lauriii, jhedstrom, Tim Bozeman, cilefen, davidhernandez, inqui, Cottser, xjm: Use the Classy theme in the Testing profile
Issue #2363139 by Wim Leers, dawehner, larowlan: _content controllers may only return render arrays, not strings.
Issue #2347465 by tim.plunkett, dawehner, cilefen: Convert all instances of #type link/links to convert to use routes.
Issue #2325571 by asif_khan, omers | dawehner: Replace _theme() calls by calls to \Drupal::theme()->render().
Issue #2031301 by andypost, Cottser, xjm, mark.labrecque, mariacha1, joelpittet, robynlgreen, danquah, trogels, Eric_A, thedavidmeister, jenlampton: Replace theme_more_link() and replace with #type 'more_link'.
Issue #2317557 by dawehner, Cottser, joelpittet, jhodgdon: Fixed renderInline not compatible with twig_auto_reload.
Issue #2238217 by effulgentsia, neclimdul, martin107, tim.plunkett, cweagans, kim.pepper, xjm: Introduce a RouteMatch class.
