Simple API endpoints for pkgctl

[jelly]

I want to:

• Adopt a package
• Disown a package
• Complete a package on a To Do list
• Signoff a package
• List signoffs

[christian-heusel]

Is anybody up to work on these? I'd love to include functionality for this in one of the coming devtools releases 😊 😍
Maybe @muflone, @jelly or @lahwaacz would be able to do this from a technical perspective..?

Also isn't @raffomania looking into this aswell due to the ToDo List integration?

[raffomania]

We talked about it a bit on the summit, I think the result was that we'd need some way to do auth first - #469 would be a good place to start, I think :)

[lahwaacz]

I can definitely help with the API, but not really with the auth...

One question, though: do we want to do it from scratch in pure Django or rather integrate with something like django-rest-framework?