Create docs/API Reference

[lopezjuanma96]

Context Opening the Repository for Public access and contribuiting.

Causes/Justification This will be useful for both users to discover how to make use of the API and developers to know how the API is structured to improve it.

Solution Alternatives

• [x] Use swagger-ui-express and create a swagger.config.json
• [x] Deploy the resulting docs on a GET endpoint at realiser/docs
• [x] Add links on README.

Repercussions

• [x] Since the API will have restricted use, we should find a way to restrict it's use on the Swagger UI to avoid overuse and extra expenses from the GCP

[lopezjuanma96]

disabled the try it out button inside swagger's documentations, so that users only get the information on how to use it but have to try it out on a separate interface, following the readme file

[lopezjuanma96]

finished adding query parameters and defaults