Add py-jupyterlab_server 1.0.0

The application author creates a JupyterLab build on their machine using the
core JupyterLab application. They can then serve their files by subclassing the
LabServerApp with the appropriate configuration and creating a Python entry
point that launches the app.

WWW: https://jupyter.org/
WWW: https://github.com/jupyterlab/jupyterlab_server