```ruby
class Nmap < Cask
  url 'http://nmap.org/dist/nmap-6.40-2.dmg'
  homepage 'http://nmap.org/'
  version '6.40-2'
  sha256 '3908c038bde3c6c5775021a3808835ea6297057747ff609d41fa89528d904582'
  install 'nmap-6.40-2.mpkg'
end
```

Add uninstall stanza for NMap
user
```ruby
class Nmap < Cask
  url 'http://nmap.org/dist/nmap-6.40-2.dmg'
  homepage 'http://nmap.org/'
  version '6.40-2'
  sha256 '3908c038bde3c6c5775021a3808835ea6297057747ff609d41fa89528d904582'
  install 'nmap-6.40-2.mpkg'
  uninstall :pkgutil => 'org.insecure.nmap6402.*.pkg'
end
```
assistant