`numfinder` scans for nameservers incrementally to find the first available numerical domain

WARNING: It's usually inaccurate because a registered domain can (and many do) have no nameservers

Examples:
- Scan `.com` and `.eu`:
  `python3 main.py com eu`
- Scan `.rocks` from 100 up to 1000:
  `python3 main.py --min 100 --max 1000 rocks`