Issue #3502361 by dpi: Initial features

.cspell-project-words.txt

.gitlab-ci.yml

LICENSE.md

Makefile

composer.json

notifier.info.yml

notifier.services.yml

phpcs.xml

phpstan.neon

src/NotifierCompilerPass.php

src/NotifierServiceProvider.php

tests/modules/notifier_test/notifier_test.info.yml

tests/modules/notifier_test/notifier_test.services.yml

...otifier_test/src/Notifier/Channel/NotifierTestChannel.php

...otifier_test/src/Notifier/Message/NotifierTestMessage.php

...ier_test/src/Notifier/Transport/NotifierTestTransport.php

...s/modules/notifier_test/src/NotifierTestMessageBuffer.php

tests/modules/notifier_test/src/NotifierTestRecipient.php

...ules/notifier_test/src/NotifierTestRecipientInterface.php

tests/src/Kernel/NotifierTest.php