* correctly pass secrets to workspace-containers

* update README
* helper-scripts with create symlinks helper and get composer auth github token helper

docker-compose.base.yml

@@ -44,6 +44,10 @@ services:
       - ${PROJECTS_DIR}:/var/www
     extra_hosts:
       - "dockerhost:${DOCKER_HOST_IP}"
+    secrets:
+      - user_ssh_key
+      - user_known_hosts
+      - composer_auth
   db:
     image: mariadb
     restart: always
@@ -70,3 +74,11 @@ services:
 # Must be copied into main docker-compose yml-file
 volumes:
   database:
+
+secrets:
+  user_ssh_key:
+    file: ~/.ssh/id_rsa
+  user_known_hosts:
+    file: ~/.ssh/known_hosts
+  composer_auth:
+    file: ~/.composer/auth.json