Merge pull request #12929 from totten/master-theming-rb

CRM/Admin/Form/Preferences/Display.php

CRM/Core/Resources.php

CRM/Utils/Hook.php

Civi/Core/Container.php

Civi/Core/Themes.php

Civi/Core/Themes/Resolvers.php

settings/Core.setting.php

templates/CRM/Admin/Form/Preferences/Display.hlp

templates/CRM/Admin/Form/Preferences/Display.tpl

tests/extensions/test.extension.uitest/files/foo.css

tests/extensions/test.extension.uitest/files/ignoreme.css

tests/extensions/test.extension.uitest/info.xml

tests/extensions/test.extension.uitest/uitest.php

tests/phpunit/Civi/Core/Theme/judy/css/bootstrap.css

tests/phpunit/Civi/Core/Theme/judy/css/civicrm.css

tests/phpunit/Civi/Core/Theme/liza/css/bootstrap.css

tests/phpunit/Civi/Core/Theme/liza/css/civicrm.css

tests/phpunit/Civi/Core/Theme/liza/css/civicrm.min.css

.../Civi/Core/Theme/liza/test.extension.uitest-files/foo.css

tests/phpunit/Civi/Core/ThemesTest.php