Adding command line tools support for user api keys

Ok, looping back to this…

I’ve put something together here : https://github.com/cfitz/discourse/commit/f5c631d6c4b327cac11d496966d5e394587add6d

Makes the auth_redirect param optional, so that the payload will just be returned after the UserApiKey is created.

Does this look alright?
Should I add something to allow admins to disable this feature? Should I add some additional text to be displayed in the new.html.erb?

thanks!