Enhanced response handling

[Aehmlo]

I would like to handle the responses from the API a little further than the current "hand off the raw data to the consumer" approach manages. For instance, I'd like to be able to tell the user they're using an invalid token, or that their color is invalid. I'll probably do this by looking at the possible responses to each request as documented in the API docs and covering just those at first.

[Aehmlo]

Closed in d1a016d.