Add task for installing scanner library
user
```ruby
namespace sanescan do
    desc "Install sane library for scanners"
    task :sanescan do
        version = "sane-backends_1.0.23"
        url = "https://launchpad.net/ubuntu/+archive/primary/+files/#{version}.orig.tar.gz"
        install_tar(url, version)
    end
end

```
assistant