See the [PyYAML](http://pyyaml.org/wiki/PyYAMLDocumentation) docs for more information as to flow
style. Essentially it should make sure the `conf.yaml` file is greppable, which may be necessary for
IP address whitelisting.
In order to whitelist IPs allowed to connect to notebooks, we need to know who the remote target
connecting is. We can blacklist on IP address only, as we have no way of authenticating them. While
we do have access to other information like cookies, we have no SSL nor way to know what
authentication method the galaxy server will be using.
The original version actually failed for me. I am led to believe that all the pipes were being
passed to netstat as it said "I don't understand the option ':'" which came from the cut command.
At the cost of simplicity, this should do what we want properly. Alternatively we could move the
awk/cut/sort into python.
`request` provides a `host_url` like "fqdn:port" from which we can extract the FQDN that this server
was accessed at. This is important so that we are accessing the IPyNB on the correct host.
Rather than assigning a static notebook signature, this has been replaced with a randomly,
deterministically generated notebook signature. This is currently done off of the dataset's id,
encoded through trans (so it's the unique hash, and not just the number), however this will need to
be exchanged for history_id whenever we have access to that.
Eric Rasche