Convert specs to RSpec 2.99.0 syntax with Transpec

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

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

For more details: https://github.com/yujinakayama/transpec#supported-conversions