first draft of adding graduates data endpoint

[nilarte]

No description provided.

[nilarte]

I have not tested this with actual graduates data yet.
That's a next step to be done.
Still please check we are on right path.
@alexeygrigorev

[alexeygrigorev]

Overall looks good. We also need to add tests and add some fake profiles so this endpoint actually returns something

[alexeygrigorev]

thanks a lot - amazing work! just need to create tests =)

[alexeygrigorev]

Thank you!