Pulls content exported from Buku, so I don't have to commit every time I
add a bookmark.
Since I added another nav item, I had to adjust the navbar css.
Update the Makefile to download the old version of the site, run
static-webmentions, and collect the WebMentions to send in a json file
saved as a build artifact.
Don't send these automatically; just save them for now. Until I work out
a solution to save sent WebMentions and avoid sending duplicates, I'll
keep the sending of WebMentions manual.
For some reason this caused webhint's axe/aria test to error out with a
"Protocol error" so I disabled it. Axe tests are covered by Lighthouse
anyway.
