Issues in setup guide

Several issues with the Setup stage

* The links point to the location in a github repository, _not_ to the raw files themselves
The CSV link currently goes to https://github.com/iaine/humanities-lesson-data/blob/master/data/openrefine/openrefine.csv
It should ideally point to the raw equivalent, https://raw.githubusercontent.com/iaine/humanities-lesson-data/master/data/openrefine/openrefine.csv
That would allow users to either save the web page, or right-click -> save as, instead of having to navigate the Github interface. Likewise for the .db file
* The guide says nothing about where to download these files _to_. Obviously, that depends a bit on the user's local environment. However, the user needs to know where it is relative to their notebook in order to open the files.
On Windows 10, the default download location is `C:\Users\\Downloads\`, while most likely, Jupyter will be opened from `C:\Users\\` (i.e. the home directory). This probably just needs a warning that the user needs to know _where_ the file is, but since Windows 10 actively hides the real path of folders like `Downloads`, it is a likely pain point for inexperienced users.
* Workshops 7 and 9 specify using `bokeh` and `sqlite` Python libraries which are not included in the installation step, and are not installed by default (in a fresh conda environment, at least) . Both are available via the `conda-forge` channel, so can be included in the same line with `ggplot`
* `ggplot` doesn't seem to be used at all. It's installed in the setup, referenced in workshop 7 (plotting with bokeh) and never used.