remove cruft
Convert specs to RSpec 3.0.3 syntax with Transpec

This conversion is done by Transpec 2.3.6 with the following command:
    transpec -b true,false -f

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

* 12 conversions
    from: be_true
      to: be true

* 9 conversions
    from: be_false
      to: be false

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

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

For more details: https://github.com/yujinakayama/transpec#supported-conversions
RuboCop
Update tested Rubies
Merge pull request #7 from square/rbx

cleanup and test on more rubies