Enable the Run All button
This in principle can be done by installing this extension: https://github.com/wallneradam/jupyterlab-run-all-buttons
However it does not work yet with Jupyterlab 2.0:
jupyter labextension install @wallneradam/run_all_buttons
An error occured.
ValueError: The extension "@wallneradam/run_all_buttons" does not yet support the current version of JupyterLab.
See: https://github.com/wallneradam/jupyterlab-run-all-buttons/issues/2