Improve UI

- Output number of blocked domains.
- Support `off` alias with double dash prefix.
- Remove date warning on macOS.
- Decrease amount of information displayed when checking for updates.
- Unify punctuation.
- Simplify code logic.

Update source file to HTTPS

Add `--force`

Use temporary file for downloads
Improve `off` UX

Fix updates

Save and restore hosts file rather than erasing it

First public release