Add authorization with Management portal using authorization-code

[nivemaham]

We need a systematic way to authenticate users for rest-auth.
We have to add support to login with Management Portal auth using authorization-code flow.
@mpgxvii would you be able to take a look at the front-end side?
@yatharthranjan @blootsvoets Have we done anything on this topic? I guess not yet. Am I right?

[yatharthranjan]

@nivemaham no we have not made any start on this yet but it is listed as one of the points in issue #13

[yatharthranjan]

We can use the radar-spring library to provide authorization in the backend.

[blootsvoets]

This was fixed with #55.