Refactor Docker Compose configuration and add email backend documentation

documentation/docs/Configuration/email_backend.md

@@ -0,0 +1,28 @@
+---
+sidebar_position: 2
+---
+
+# Change Email Backend
+
+To change the email backend, you can set the following variable in your docker-compose.yml under the server service:
+
+## Using Console (default)
+
+```yaml
+environment:
+  - EMAIL_BACKEND='console'
+```
+
+## With SMTP
+
+```yaml
+environment:
+  - EMAIL_BACKEND='email'
+  - EMAIL_HOST='smtp.gmail.com'
+  - EMAIL_USE_TLS=False
+  - EMAIL_PORT=587
+  - EMAIL_USE_SSL=True
+  - EMAIL_HOST_USER='user'
+  - EMAIL_HOST_PASSWORD='password'
+  - DEFAULT_FROM_EMAIL='user@example.com'
+```