add firefly displays to wip notebook

[stargaser]

Work in Progress: a tutorial-firefly notebook based on the notebook in the answers branch

[TallJimbo]

@stargaser, you should now have permission to push to the main repo if you'd like.

I'd also be interested in trying this out myself. First stumbling block is getting firefly_client and display_firefly into the JupyterLab environment - it looks like display_firefly expects to build against a eups-managed firefly_client, but firefly_client doesn't have an ups directory.

[stargaser]

Thanks for the permissions -- it might be better to make a "firefly" branch like we discussed.

For display_firefly, @SimonKrughoff came up with a workaround for the tutorial environment. Place these lines into $HOME/notebooks/.user_setups:

export PYTHONPATH=/home/shared/packages/lib/python3.5/site-packages/:$PYTHONPATH
setup -r /home/shared/packages/display_firefly

The ups tables for firefly_client are on the lsst-dev branch -- same setup as for starlink-ast, xrootd and oorb packages (detailed in RFC-248). firefly_client is also pip-installable. display_firefly and its dependencies are properly represented in repos.yaml and builds with rebuild and in the continuous integration environment.