add Dockerfile and adjust readme to reflect a quick start

Dockerfile

@@ -0,0 +1,18 @@
+FROM jupyter/base-notebook:python-3.7.6
+
+
+USER root
+
+RUN apt-get -y update \
+ && apt-get install -y dbus-x11 \
+   firefox \
+   xfce4 \
+   xfce4-panel \
+   xfce4-session \
+   xfce4-settings \
+   xorg \
+   xubuntu-icon-theme
+
+USER $NB_USER
+RUN conda install -c manics websockify \ 
+ && pip install jupyter-desktop-server

README.md

@@ -4,3 +4,46 @@
 Run XFCE (or other desktop environments) on a JupyterHub.
 
 This is based on https://github.com/ryanlovett/nbnovnc and a fork of https://github.com/manics/jupyter-omeroanalysis-desktop
+
+
+## Docker 
+
+To spin up such a notebook, please build and run the container like this.
+
+```bash
+$ docker build -t $(whoami)/$(basename ${PWD}) .
+Sending build context to Docker daemon  36.76MB
+Step 1/5 : FROM jupyter/datascience-notebook:latest
+**snip**
+Successfully installed aiohttp-3.6.2 async-timeout-3.0.1 jupyter-desktop-server-0.1.2 jupyter-server-proxy-1.5.0 multidict-4.7.6 simpervisor-0.3 yarl-1.4.2
+Removing intermediate container ed906d6b1074
+ ---> 826211e74ce1
+Successfully built 826211e74ce1
+Successfully tagged myname/jupyter-desktop-server:latest
+$ 
+```
+
+Now you can ran the image:
+
+```bash
+$ docker run --rm  -p 8888:8888 $(whoami)/$(basename ${PWD})
+Executing the command: jupyter notebook
+[I 12:43:59.148 NotebookApp] Writing notebook server cookie secret to /home/jovyan/.local/share/jupyter/runtime/notebook_cookie_secret
+[I 12:44:00.221 NotebookApp] JupyterLab extension loaded from /opt/conda/lib/python3.7/site-packages/jupyterlab
+[I 12:44:00.221 NotebookApp] JupyterLab application directory is /opt/conda/share/jupyter/lab
+[I 12:44:00.224 NotebookApp] Serving notebooks from local directory: /home/jovyan
+[I 12:44:00.225 NotebookApp] The Jupyter Notebook is running at:
+[I 12:44:00.225 NotebookApp] http://924904e0a646:8888/?token=40475e553b7671b9e93533b97afe584fa2030448505a7d83
+[I 12:44:00.225 NotebookApp]  or http://127.0.0.1:8888/?token=40475e553b7671b9e93533b97afe584fa2030448505a7d83
+[I 12:44:00.225 NotebookApp] Use Control-C to stop this server and shut down all kernels (twice to skip confirmation).
+[C 12:44:00.229 NotebookApp]
+
+    To access the notebook, open this file in a browser:
+        file:///home/jovyan/.local/share/jupyter/runtime/nbserver-8-open.html
+    Or copy and paste one of these URLs:
+        http://924904e0a646:8888/?token=40475e553b7671b9e93533b97afe584fa2030448505a7d83
+     or http://127.0.0.1:8888/?token=40475e553b7671b9e93533b97afe584fa2030448505a7d83
+*snip*
+```
+
+Now head to the URL shown and you will be greated with a XFCE desktop.