Bump RSpec from 1.3 to 3.1

- Update spec_helper
- Update rake task for running specs
Convert specs to RSpec 3.1.7 syntax with Transpec

This conversion is done by Transpec 2.3.8 with the following command:
    transpec -f spec

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

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

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

* 26 conversions
    from: it { should ... }
      to: it { is_expected.to ... }

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

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

* 21 conversions
    from: obj.stub(:message => value)
      to: allow(obj).to receive_messages(:message => value)

* 19 conversions
    from: be_true
      to: be_truthy

* 19 conversions
    from: its(:attr) { }
      to: describe '#attr' do subject { super().attr }; it { } end

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

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

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

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

* 6 conversions
    from: stub('something')
      to: double('something')

* 5 conversions
    from: be_false
      to: be_falsey

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

* 4 conversions
    from: lambda { }.should_not
      to: expect { }.not_to

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

* 2 conversions
    from: obj.stub_chain(:message1, :message2)
      to: allow(obj).to receive_message_chain(:message1, :message2)

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

* 1 conversion
    from: it { should_not ... }
      to: it { is_expected.not_to ... }

For more details: https://github.com/yujinakayama/transpec#supported-conversions
Fix ssl_spec
Replace describe with RSpec.describe

Disabled monkey patching
Fix connection_adapter_spec
Fix syntax for response_spec
Fix request_spec
Fix most of httparty_spec
Merge pull request #1 from mikeastock/mas/rspec_3_upgrade

RSpec 3 Upgrade