Fix database behavior
Using the --database flag just print the help and exit with code 1 but no specific error.
This PR fix this issue and set a better default for the db (~/.config/tool is not a good place for data).
The standard is ~/.local/share/tool, checking the XDG_DATA_HOME env var first can help.
Thank you for noticing, I've opened issue #6 to track that bug. Unfortunately I cannot accept the PR at the moment: while I agree that .config wasn't the wisest choice moving it to .local/share would be a breaking change that I'm not willing to accept at the moment. I'd be glad to have the bug fix part though.
Do you want 2 distinct PR?
Removed the xdg stuff