Added field for a 'badge awarding badge'

[askvictor]

No description provided.

[willkg]

I don't understand what this pull request is doing. Can you explain the motivation behind this? What's the use-case example for auto-awarding a badge when only some of the prerequisites have been met?

[askvictor]

oops; stuffed up my PR. This is a different feature to #171 - it should create a field which references a badge, which, when held by the user, allows them to award the current badge. Think of it like badge-based permissions. I'll try to get the PR fixed up soon, but might not have time in the very near future.

[willkg]

Ahh... got it! Yeah, I'll keep an eye out for the fixed PR. Thank you for clarifying!

[lmorchard]

My feedback here is similar to the prereqs PR - that is, this logic probably would be happier living in a badges.py as a signal handler.

Of course, that doesn't give us the extra field added to the model. I think that's fine for a site that has most of its badges defined in badges.py - you can just encode the relationships there. But, for a "multiplayer" site like badges.mozilla.org, we might need some thought behind how to store this relationship if the core model isn't extended.