Rewrite bootstrapper in Python

- This was going to get too complex for bash. Only way to
  kill those scripts is before they get too complex.
- Better progress messages from bootstrapper.
- Differentiate between bootstrapper & installer
- Cleanup documentation a little bit

README.rst

@@ -18,14 +18,5 @@ more information.
 Quick Start
 -----------
 
-On a fresh Ubuntu 18.04 server, you can install The Littlest JupyterHub with:
-
-.. code-block:: bash
-
-   curl https://raw.githubusercontent.com/yuvipanda/the-littlest-jupyterhub/master/installer/install.bash | sudo bash -
-
-This takes 2-5 minutes to run. When completed, you can access your new JupyterHub
-at the public IP of your server (on the default http port 80)!
-
-For more information (including other installation methods), check out the
-`documentation <https://the-littlest-jupyterhub.readthedocs.io>`_.
+Install The Littlest JupyterHub (TLJH) in under 10 minutes by following the
+`quickstart tutorial <http://the-littlest-jupyterhub.readthedocs.io/en/latest/tutorials/quickstart.html>`_.