add Settings class and Twig cache settings

docker/.env.development

@@ -0,0 +1,4 @@
+# .env.development: Environment variables for local development
+
+# Disable Twig cache
+TWIG_CACHE_DIR=

docker/.env.testing

@@ -0,0 +1,4 @@
+# .env.testing: Environment variables for testing deployment
+
+# Disable Twig cache -- TODO enable cache
+TWIG_CACHE_DIR=

docker/docker-compose.local.yml

@@ -8,5 +8,7 @@ services:
     restart: always
     ports:
       - 8080:80
+    env_file:
+      - .env.development
     volumes:
       - ../:/var/www/

docker/docker-compose.testing.yml

@@ -6,6 +6,8 @@ services:
       context: ..
       target: production
     restart: always
+    env_file:
+      - .env.testing
     networks:
       - traefik
     labels: