Add advanced training modules

[alimanfoo]

We are planning to begin creating and adding advanced level training modules to the course website. These will deal with more complex topics, beyond what is already covered in the existing 8 workshops.

The existing 8 workshops will be maintained and will form the corpus for an "entry-level" data analysis training course. These will also be used when we run the entry-level course via Zoom.

The "advanced-level" training modules will be standalone modules that trainees can undertake as self-directed learning. We will likely not include them in the course via Zoom, rather they will be optional extensions that trainees can undertake if they wish to.

In the training course website each workshop is organised as a "part" within the jupyter book table of contents. I propose we place new advanced-level modules within a new "part" in the same website, called something like "Advanced analysis".

Suggestions for advanced analysis modules will be raised as new issues on this github repo and should be labelled "advanced".