Extend gitignore for macos & add development notes to readme

.gitignore

@@ -124,3 +124,8 @@ docker/test/db
 docker/development/media
 docker/production/media
 docker/test/media
+
+# MacOS
+.DS_Store
+.AppleDouble
+.LSOverride

README.md

@@ -23,8 +23,58 @@ docker.env files.
 
 The following can be useful in case that automatic migrations throw errors.
 
-1. delete everything in the migrations folder except for __init__.py.
-2. drop into my MySQL console and do: DELETE FROM django_migrations WHERE app='my_app'
+1. delete everything in the migrations folder except for `__init__.py`.
+2. drop into my MySQL console and do: `DELETE FROM django_migrations WHERE app='my_app'``
 3. while at the MySQL console, drop all of the tables associated with my_app.
-4. re-run ./manage.py makemigrations my_app - this generates a 0001_initial.py file in my migrations folder.
-5. run ./manage migrate my_app - I expect this command to re-build all my tables, but instead it says: "No migrations to apply."
+4. re-run `./manage.py makemigrations my_app` - this generates a 0001_initial.py file in my migrations folder.
+5. run `./manage migrate my_app` - I expect this command to re-build all my tables, but instead it says: "No migrations to apply."
+
+
+# Development Notes
+
+## Information
+
+- default user wie vergeben in Schritt 3 [Development Setup > docker](#docker)
+
+## Development Setup 
+
+### docker
+
+```bash
+# 1. Clone repository (see above)
+
+# 1.2 Load Submodules
+git submodule update --init
+
+# 2. Install dependencies (docker, docker compose)
+
+# 3. Create default (super)user
+docker compose exec master bash -c "cd jdav_web && python3 manage.py createsuperuser"
+
+# 4. Setup development environment 
+export GID=${GID}
+export UID=${UID}
+
+# 5. Start docker compose
+cd docker/development
+docker compose up -d
+```
+
+Erläuterungen:
+- zu 2.: Im docker compose sollen die gleichen Nutzerrechte vorliegen, wie auf der entwickelnden Maschine um auto rebuild zu ermöglichen. Damit 
+
+
+### Known Issues
+
+- Bei `docker compose up -d` des development [docker-compose.yaml](docker/development/docker-compose.yaml)
+
+  ```bash
+   => ERROR [master 6/7] RUN groupadd -g  kasimir && useradd -g  -u  -m -d /app kasimir                                                                                                                0.2s
+  ------
+   > [master 6/7] RUN groupadd -g  kasimir && useradd -g  -u  -m -d /app kasimir:
+  0.141 groupadd: invalid group ID 'kasimir'
+  ------
+  failed to solve: process "/bin/sh -c groupadd -g $GID $USER && useradd -g $GID -u $UID -m -d /app $USER" did not complete successfully: exit code: 3
+  ```
+
+  - Dieser Fehler entsteht, wenn Schritt 2 im Abschnitt [Development Setup > docker](#docker) übersprungen wird.