Needs updating for the latest IndieAuth changes

[fluffy-critter]

As of this past weekend, requesting an id has been deprecated in favor of requesting a code with no scope.

SelfAuth (formerly-correctly) responds with an error in the latter case, and it seems to be the only commonly-used endpoint which does, which makes for a difficult incompatibility with this protocol change since there's no way for the client to even know a scopeless code request failed and needs to fall back to an id request.

[sknebel]

Seems like that's #46 ?

[fluffy-critter]

Ah, so it is! Bit of a race condition -- I had drafted this issue last night but didn't get around to submitting it until just now, and in the meantime a pull request got opened. :) I guess I can close this issue then.