ChRIS client for Jupyter Notebooks

With [chrs](https://github.com/FNNDSC/chrs) succeeding caw, the `chris` module of caw is still useful in the context of Jupyter notebooks. Perhaps developmental effort should be focused on providing a good client.

The issue identifies caw's chris module, the chrs project, and Jupyter notebooks as the relevant context, but names no files, tests, or concrete client behavior. Start by locating the chris module and comparing it with chrs; the scope and acceptance criteria for a usable notebook client still need to be defined.

Written by the indexing model from the issue text.