Register form and confirmation messages

configuration/base.yaml

@@ -1,14 +1,6 @@
 application:
   port: 8000
 database:
-  host: "127.0.0.1"
-  port: 5432
-  username: "postgres"
-  password: "password"
   database_name: "newsletter"
 email_client:
-  base_url: "http://127.0.0.1"
-  sender_email: "sender@example.com"
-  authorization_token: "my-secret-token"
   timeout_milliseconds: 10000
-redis_uri: "redis://127.0.0.1:6379"