Add build command for development container

projects/docker/README.md

@@ -111,7 +111,7 @@ Be aware of the `touch .history` command before `docker run`. This makes sure a
 
 ### Build the development Docker container
 
-The [Dockerfile](./Dockerfile) has an additional build argument, `ADD_DEV`. If set to `YES`, the follwoing development tools are added to the Docker image:
+The [Dockerfile](./Dockerfile) has an additional build argument, `ADD_DEV`. If set to `YES`, the following development tools are added to the Docker image:
 
 - [Emacs](https://www.gnu.org/software/emacs/)
 
@@ -121,6 +121,14 @@ The [Dockerfile](./Dockerfile) has an additional build argument, `ADD_DEV`. If s
 
 None of these are needed to run a translation script.
 
+The build argument is just added to the `docker build` call:
+
+```terminal
+$ # DOCKER_BUILDKIT=1 is only needed for older versions of Docker.
+$ DOCKER_BUILDKIT=1 docker build -f docker/Dockerfile --build-arg MMCIF_USER_ID=1234 --build-arg ADD_DEV=YES -t converter:latest .
+$
+```
+
 For working on a translation script, it is convenient to mount the complete Git repository when running the Docker container interactively. This makes sure `pyproject.toml` is available from the repository root to `black` and `pylint`:
 
 ```terminal
@@ -132,5 +140,6 @@ $
 In the session, the Git repository can be found in `/develop`.
 
 <!--  LocalWords:  TOC modelcif cd whoami localuser uid arg CONVERTERSCRIPT
-      LocalWords:  CONVERTERCMD cif ASFVG BUILDKIT pwd
+      LocalWords:  CONVERTERCMD cif ASFVG BUILDKIT pwd DEV Pylint pyproject
+      LocalWords:  toml pylint
  -->