Add Sweet Home 3D (Version 4.0) Cask
user
```ruby
class SweetHome3d < Cask
  url 'http://downloads.sourceforge.net/project/sweethome3d/SweetHome3D/SweetHome3D-4.0/SweetHome3D-4.0-macosx.dmg'
  homepage 'http://www.sweethome3d.com/'
  version '4.0'
  sha1 '15b0ec1d8b70267707b00637ac7289cf8267f15d'
  link :app, 'Sweet Home 3D.app'
end
```
assistant