… a man-page containing all of gallery-dl's configuration file options.
This implementation relies on Python dicts preserving their insertion
order. Python 3.4 and 3.5 need to use OrderedDict or they produce
randomly ordered man-page sections.
The man-page formatting is a bit rough around the edges, but it works
for the most part. The only real "problem" are inline-links, but it's
better if they are left in there.
