Sector doesnt validate

[paulsp94]

Current behavior

You can Post a Sector with the same Name and Organization to the API which should not be possible as it would be redundant.

Expected behavior

It should refuse the Post Request by saying that there already exists a Sector with the same Name and Organization.

Steps to reproduce the behavior

1. Post Sector with same Name and Organization as an already existing one to the API.

[rafa-munoz]

I agree it's not a good behaviour.

This should make the job:

class Meta:
    unique_together = (..)