Convert specs to the latest RSpec syntax with Transpec

This conversion is done by Transpec 1.3.0 with the following command:
    transpec --force --generate-commit-message

* 2161 conversions
    from: obj.should
      to: expect(obj).to

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

* 56 conversions
    from: obj.should_receive(:message)
      to: expect(obj).to receive(:message)

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

* 26 conversions
    from: =~ /pattern/
      to: match(/pattern/)

* 20 conversions
    from: be_true
      to: be_truthy

* 15 conversions
    from: lambda { }.should
      to: expect { }.to

* 9 conversions
    from: obj.stub!(:message)
      to: allow(obj).to receive(:message)

* 9 conversions
    from: obj.should_not_receive(:message)
      to: expect(obj).not_to receive(:message)

* 7 conversions
    from: < expected
      to: be < expected

* 6 conversions
    from: be_false
      to: be_falsey

* 5 conversions
    from: expect { }.not_to raise_error(SpecificErrorClass)
      to: expect { }.not_to raise_error

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

* 2 conversions
    from: mock('something')
      to: double('something')

* 1 conversion
    from: obj.stub!(:message => value)
      to: allow(obj).to receive(:message).and_return(value)

* 1 conversion
    from: lambda { }.should_not
      to: expect { }.not_to

* 1 conversion
    from: === expected
      to: be === expected