Decide what to do with the left ('primary') sidebar

[JoeZiminski]

At present the primary sidebar on the left of pages is not used for anything, meaning it shows blank. There are a few different things we could do, for example just remove it on every page (conf.py):

html_sidebars = {
    "**": [],
}

or include a 'globaltoc' that shows the position in the overall website, but to me it looks a little strange:

html_sidebars = {
    "**": ["globaltoc.html"],
}

Current:

Without:

globaltoc

[niksirbi]

We are using it on the "Get Involved" page. So if we remove it, we'll have to do a bit of restructuring.
Altenatively, we could also restructure things in a way that uses the primary sidebar.
But totally fine with removing it (I agree it looks strange to have it empty).