Feature/latest news

- Added ability to create an CMS page as an article. 
    - Besides adding the actual content to the page, you are expected to use the Article plugin to create an Article object. This Article object has the information such as the title, summary, published date, etc. Using this Article plugin is very important. We can discuss this part in details if something is not that clear.

- Added an endpoint to retrieve the latest news. By default if nothing is provided to the endpoint, two latest published article objects would be retrieved. The endpoint can also retrieve latest news related to a specific tournament, if tournament slug is being passed in the GET request. It's also possible to control the number of articles by passing a 'limit' parameter.
Could you explain why we would need this? Could we not just add a field on the Searializer class?