requirering the facter/util/debian.rb module causes
puppet warnings on wheezy hosts, and custom facts like
`$::debian_codename` cannot be evaluated.
warning: Could not load fact file
/srv/dev/projects/puppet/shared-modules//apt/lib/facter/debian_nextcodename.rb:
no such file to load -- facter/util/debian
Removing the require line solves this.
* Removes dependency on lsb-release and/or Facter >1.7
(values are based on $::lsbdistcodename, when available)
* Simplifies maintenance: only lib/facter/util/* require updates as new
releases are made
Caveats:
* apt::codename is removed; to override debian_* facts, set the
FACTER_debian_codename environment variable for puppet
* If tracking unstable, make sure lsb-release is installed, as other
methods can't tell between testing and unstable
