Check in Ubuntu Utopic Ruby Highline source pkg

Check in the source package for Ubuntu Utopic's Ruby Highline, ready for
backporting to Precise.

Downloaded from:
http://archive.ubuntu.com/ubuntu/pool/universe/r/ruby-highline/ruby-highline_1.6.20-1.debian.tar.gz
Backport Ruby Highline to Ubuntu Precise
Relax dependency on gem2deb

The latest available version of `gem2deb` for Ubuntu Precise is `0.2.13`
and this package builds correctly with that version, so relax the
dependency.
Update maintainer and uploaders in control file
Merge pull request #50 from alphagov/64650014-ruby-highline

[#64650014] Backport Ruby Highline to Ubuntu Precise