Normalize Gemfile & pin tests to rspec < 2.99

Pin to rspec < 2.99 until rspec-puppet officially supports rspec 3.x.
This is to avoid warnings due to deprecated matchers in the
rspec-puppet gem.

This change is also intended to normalize the Gemfile for all stackforge
puppet modules.  This should facilitate pinning gem versions when
releasing new stable branches, since the same diff can be used for all
repos.

Change-Id: Ie36f3537c46a86e6d3d00ebd9abf62b44dbe0540
Partial-Bug: #1326034
Merge "Normalize Gemfile & pin tests to rspec < 2.99"