Fix CLI to generate swagger.json compatible with API Management

[EliuX]

Right now we have can generate a swagger.json running something like

python cli.py gen_swagger_json -f ~/Downloads/swagger.json

but this generated file is not compatible with API Management and we need to make this possible in order to keep there an updated definition of Swagger and allow Azure to generate to corresponding Swagger UI.
Also allowing Azure to understand this definition will allow us to define policies for the API, which applies for the whole application.

TODO:

• Change the CLI command in order to change the generated swagger.json in a way it can be directly exported to API Management. You will probably need support from colleagues which has already successfully applied this change, like @juanultimate or @fabidick22.
• Coordinate with DevOps or create another ticket to automate the deployment of this definition in every deployment of the API.

[EliuX]

After a meeting, between @enriquezrene, @juanultimate, @fabidick22, @Angeluz-07 and I, we verified and came to the conclusion that:

• The swagger.json that is currently generated can be understood by Azure API Management to generate the Swagger UI and understand the interface of the app
• Azure API Management is not capable to generate multiple examples by this swagger.json, so they have to be added manually. Therefore, we decided that if a definition is added via Python/Flask/Restplus, ahead to its implementation, that definition should return random examples using the library Faker.