feat: new configuration system (and schema) (#2819)

docker/ci-config/postal.test.yml

@@ -1,42 +0,0 @@
-general:
-  use_ip_pools: false
-
-web_server:
-  bind_address: 127.0.0.1
-  port: 5000
-
-smtp_server:
-  port: 2525
-
-main_db:
-  host: mariadb
-  username: root
-  password:
-  database: postal
-
-message_db:
-  host: mariadb
-  username: root
-  password:
-  prefix: postal
-
-dns:
-  mx_records:
-    - mx.postal.example.com
-  smtp_server_hostname: postal.example.com
-  spf_include: spf.postal.example.com
-  return_path: rp.postal.example.com
-  route_domain: routes.postal.example.com
-  track_domain: track.postal.example.com
-
-smtp:
-  host: 127.0.0.1
-  port: 2525
-  username:
-  password:
-  from_name: Postal
-  from_address: postal@yourdomain.com
-
-rails:
-  secret_key: 5e82ca222ccc8642fb38a8ea4b847408b983b42a497ec16b499ed89ba506a4edcab8ac015b32dbd1ea620119484e0c1dc056f97b4b37cd29146192df5ccd6abec345a0125c424daad12430a4796d108197c746f5eb8e9e1faa36a8ff8d0c5a9cf00191f997c354341fd656ca0ef9d7b40a37ea4b1b1e78fe9030fa9990dbb662
-  environment: test