Issue #3417517 by Grimreaper: Enable Gitlab CI + Update README + Coding standards

.gitlab-ci.yml

CHANGELOG.md

README.md

composer.json

...les/ui_patterns_ds/src/Plugin/DsFieldTemplate/Pattern.php

...ds/src/Plugin/UiPatterns/Source/DsFieldTemplateSource.php

...ts/src/FunctionalJavascript/UiPatternsFieldRenderTest.php

.../src/FunctionalJavascript/UiPatternsFieldSettingsTest.php

modules/ui_patterns_ds/ui_patterns_ds.module

modules/ui_patterns_field_group/README.md

...ugin/field_group/FieldGroupFormatter/PatternFormatter.php

...c/FunctionalJavascript/UiPatternsFieldGroupRenderTest.php

...FunctionalJavascript/UiPatternsFieldGroupSettingsTest.php

modules/ui_patterns_layouts/README.md

...s/ui_patterns_layouts/src/Plugin/Layout/PatternLayout.php

.../src/FunctionalJavascript/UiPatternsLayoutsRenderTest.php

...rc/FunctionalJavascript/UiPatternsLayoutsSettingsTest.php

modules/ui_patterns_layouts/ui_patterns_layouts.module

modules/ui_patterns_library/README.md

...ui_patterns_library/src/Plugin/Deriver/LibraryDeriver.php