Be more robust when starting notebook

[jitseniesen]

From Gitter: "I also think we should start the notebook in a more robust way. Here we assume the jupyter command is in your PATH, but we could detect if that's true or not before doing it"

[ccordoba12]

Another option would be to create a Python script that starts the notebook programatically (instead of passing options to jupyter notebook). The main class to do that is NotebookApp, I think.

Then we could start the notebook with something like:

subprocess.Popen([sys.executable, 'nb_start.py'])

[ccordoba12]

#141 is also related to this. So I'd really prefer that we'd follow my last suggestion.

[jitseniesen]

Do you have something like this PR in mind? It does not seem to require a script.

[ccordoba12]

I was thinking to use a script so that the notebook server can be started in the background with subprocess. What are you thinking to solve this issue?

[ccordoba12]

Sorry, I didn't see your referenced PR. I'm looking at it right now.