Add Chef Sugar

After seeing the PR at https://github.com/opscode/omnibus-software/pull/141/files, should we consider adding [Chef Sugar](https://github.com/sethvargo/chef-sugar) as a dependency on omnibus-ruby. Since Sugar works mostly off of Ohai data (with minimal exception), that PR could have leveraged the `freebsd?` matcher.

/cc @opscode/release-engineers @sersut @danielsdeleo @lamont-granquist