Revert "(maint) Replace rspec >= 2.11 expect(foo).to with foo.should"

This reverts commit f83db167b7147f0fe05419b4c1ee83f7b03786dc.
Revert "Merge branch 'razic-fix/2.x/17710_ipmodule_refactor'"

This reverts commit c028d611ef294f2a206e90b9268b0afa61ff0654, reversing
changes made to e189f8a7739cad36bf8130741056ebb3f4a4f766.

This change set is being reverted because we're getting the following
error when running the acceptance test suite on Microsoft Windows.

     Could not retrieve local facts: undefined method `get_interfaces'
     for Facter::Util::IP:Class
Merge branch 'revert_ipmodule_refactor'

* revert_ipmodule_refactor:
  Revert "Merge branch 'razic-fix/2.x/17710_ipmodule_refactor'"
  Revert "(maint) Replace rspec >= 2.11 expect(foo).to with foo.should"

References GH-423