Update sass to 3.3.8.
Upgrade RSpec gems to 2.99.
Fix deprecations reported by RSpec 2.99.
Convert specs to RSpec 2.99.0 syntax with Transpec

This conversion is done by Transpec 2.2.1 with the following command:
    transpec

* 44 conversions
    from: obj.should
      to: expect(obj).to

* 19 conversions
    from: == expected
      to: eq(expected)

For more details: https://github.com/yujinakayama/transpec#supported-conversions
Update RSpec gems to 3.0.
Use latest equivalent-xml to fix errors under RSpec 3.
Fix an RSpec 3 deprecation.
Merge branch 'rspec-3'