The deadline daemon is supposed to send emails
to users who have borrowed books and are supposed to deliver
them back, or users who have added themselves to the queue,
and is waiting for a book.
The scanner tool is about to become a fullfledged repl, much in the same
manner as dibbler.
Changes:
- Rename `tools/scanner.py` -> `cli/main.py`
- Create abstraction layer for Cmd with numbered commands
- Create submenu for items
- Lots of functionality edits
- Fill out more todos in REAMDE
- Migrate project to use poetry for ease of dependency management and
building
- Add wsgi prod and dev entrypoints
- Start working on a more rigid scanning tool
- Remove unused ignores in .gitignore
- Update README about changes
