Parameterise the Web vs. Gemini option
Make sure we can never run Halp with a relative Web path
Remove printf debugging
Don't concatenate Web path since we don't support relative paths
Continue fixing weird relative vs. absolute paths

The right thing here would be to have AtomFeed barf if passed a
relative path, at all.
Fix web path handling in Atom generation
Remove full pathname change
Fix Atom feed generation

I'm not expecting these tests to pass in CI first cut, because
it'll *probably* use UTC timestamps.
Start writing some unit tests for the AtomFeed module
Use the correct Web path for Atom feed generation
Adding some Atom feed fixture files for future tests
Use consistent Atom terminology for feeds
Extract MIME types into a separate module

... just because it was making me sad that every time I opened
WebServer.pm I saw a list of (not Web specific!) MIME types.
Extract Atom handling into separate module

Note that this has handily exposed another seam - file handling
utilities that should ultimately prove common to both Web and Gemini
We don't need to mkdir halp any more
Modify install script to symlink from Git clone
Fix halp rc.d script

+ Ensure the cwd is set correctly.
+ Log output using daemon.
Fix some relative paths in the install script
Fix copypasta addition of certbot call