set the root directory when starting jupyter notebooks code example

Example: set the root directory when starting jupyter notebooks

# To change the Jupyter Notebooks startup directory:
1. From the command line (shell) run: jupyter notebook --generate-config
2. View the config file at: ~/.jupyter/jupyter_notebook_config.py
3. Change the line: c.NotebookApp.notebook_dir = '' to
	c.NotebookApp.notebook_dir = '/path/to/desired/startup/directory'