Copy clone hint for docker setup

README.md

@@ -48,6 +48,9 @@ See the [README.md of the submodule](../../../../sample_applications/-/blob/mast
 
 To run via docker on any up-to-date linux system:
 
+- **Either** clone this repo and its submodules (recommended for fresh installations):
+    - as a guest: `git clone --recurse-submodules https://git-st.inf.tu-dresden.de/ceti/ros/panda_gazebo_workspace.git panda_gazebo_workspace`
+    - as a project member with a registered ssh key: `git clone --recurse-submodules git@git-st.inf.tu-dresden.de:ceti/ros/panda_gazebo_workspace.git panda_gazebo_workspace`
 - `docker build . -t ceti-panda-gazebo-workspace`
 - `./docker-run.sh roslaunch sample_applications sample_simple_simulation.launch`