Revert #406

This reverts commit 674689501fcefdfe8cfbe35e19391ebcbf6d357d, reversing
changes made to 435664829e3a8ec98aed2c38bc3f625db38b84e3.

This change set is being reverted because we're seeing the following
issue when running Facter on Linux and Darwin:

    $ facter
    Could not retrieve network_gif0: undefined local variable or method `label' for Facter::Util::IP:Module
    Could not retrieve network_en1: undefined local variable or method `label' for Facter::Util::IP:Module
    Could not retrieve network_vboxnet0: undefined local variable or method `label' for Facter::Util::IP:Module
    Could not retrieve network_stf0: undefined local variable or method `label' for Facter::Util::IP:Module
    Could not retrieve network_fw0: undefined local variable or method `label' for Facter::Util::IP:Module
    Could not retrieve network_vmnet1: undefined local variable or method `label' for Facter::Util::IP:Module
    Could not retrieve network_lo0: undefined local variable or method `label' for Facter::Util::IP:Module
    Could not retrieve network_en0: undefined local variable or method `label' for Facter::Util::IP:Module
    Could not retrieve network_p2p0: undefined local variable or method `label' for Facter::Util::IP:Module
    Could not retrieve network_vmnet8: undefined local variable or method `label' for Facter::Util::IP:Module
Merge branch 'revert_pr_406'

* revert_pr_406:
  Revert #406