Started with the RSpec upgrade

Had to add rspec-its gem
Added as it's being deprecated in RSpec 3

This is the warning:
--------------------------------------------------------------------------------
rspec-rails 3 will no longer automatically infer an example group's spec type
from the file location. You can explicitly opt-in to this feature using this
snippet:

RSpec.configure do |config|
  config.infer_spec_type_from_file_location!
end

If you wish to manually label spec types via metadata you can safely ignore
this warning and continue upgrading to RSpec 3 without addressing it.
--------------------------------------------------------------------------------
Fixes for deprecated chages for RSpec 3
Convert specs to RSpec 2.99.0 syntax with Transpec

This conversion is done by Transpec 2.3.1 with the following command:
    transpec

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

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

* 27 conversions
    from: it { should_not ... }
      to: it { is_expected.not_to ... }

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

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

* 16 conversions
    from: describe 'some model' { }
      to: describe 'some model', :type => :model { }

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

* 3 conversions
    from: describe 'some controller' { }
      to: describe 'some controller', :type => :controller { }

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

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

* 1 conversion
    from: describe 'some helper' { }
      to: describe 'some helper', :type => :helper { }

* 1 conversion
    from: describe 'some routing' { }
      to: describe 'some routing', :type => :routing { }

For more details: https://github.com/yujinakayama/transpec#supported-conversions
Upgraded RSpec to 3.0.1
Removed deprecated RSpec option

RSpec::Core::Configuration#treat_symbols_as_metadata_keys_with_true_values=

is deprecated, it is now set to true as default and setting it to false
has no effect.
Turning depreciation warnings into errors

It's for RSpec, so that I can remove them completely
Added 'rspec-legacy_formatters' gem

The reason for adding this gem is because some classes have 'puts'
statements in them. Rather than removing them right now, while upgrading
to RSpec 3, I'd leave them in and remove them later, when everything is
working.

Also removed the config that turns deprecations into exceptions.
Merge pull request #317 from ministryofjustice/rspec-upgrade

RSpec upgrade to 3