Bump rspec to 2.14
Convert specs to RSpec 2.14.7 syntax with Transpec

This conversion is done by Transpec 2.0.0 with the following command:
    transpec

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

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

* 16 conversions
    from: obj.should_not
      to: expect(obj).not_to

* 2 conversions
    from: collection.should have(n).items
      to: expect(collection.size).to eq(n)

* 1 conversion
    from: =~ [1, 2]
      to: match_array([1, 2])

See also: https://github.com/yujinakayama/transpec#supported-conversions