API versioning

## Description

> Add versioning to backend API, so endpoints URL contains v1 as a part of the path. Make sure we can keep backward compatibility, so endpoints determinate which code is called for v1 and next versions (keeping in different folders or adding parameter or any other idea).

initially brought up by @annabauza

Before implementing this I think it's important to think about this solution, so before submitting a PR for this, please let us know what you intend to do for this.

Flask RESTplus allows using Blueprints: https://flask-restplus.readthedocs.io/en/stable/scaling.html#use-with-blueprints

## Acceptance Criteria
### Update [Required]
- [ ] Come with a solution to add API versioning to backend

## Definition of Done
- [ ] All of the required items are completed.
- [ ] Approval by 1 mentor.

## Estimation
3 hours