Add initial 'eventlogging::notebook' class

IPython Notebook and PyLab provide an integrated environment for data analysis
and numerical computation in Python, comparable to Mathematica, but free and
open source.

This change contains an initial stub of an eventlogging::notebook class. My
goal is to provide a web interface for doing analytic work on EventLogging
data. The service will be served on a private interface and thus be accessible
only internally, by tunneling through bast1001 or equivalent.

I am cautious about accumulating dependencies, but I strongly believe that this
combination of tools represents the leading open-source platform for this type
of work. The packages are marked ensure => latest because the benefits of
following closely behind development seem to me to outweigh the disadvantages
in this particular case.

Change-Id: Idd28e8d2f12188f45f6de5dd7f4a8ef42ee57fd8
Merge "Add initial 'eventlogging::notebook' class" into production