Dockerfile Out-of-Date

[hydrosquall]

1. ipython/scipyserver is deprecated (see description)
2. The recommended replacement image, scipy-notebook is based on Python3, so we'd want to specify the older image, and figure out how to launch the notebook from a virtualenv from within the docker container
3. It's debatable whether one might just want to upgrade all these examples to Python3 rather than sort through the docker situation described above.