Start moving toward a consolidated field mapping.

There's still some additional complexity I hope to start hiding, but I
think this is the way to go forward---anything that deals with posts
can start decorating this structure with its own bits, rather than
having to maintain multiple somewhat-duplicative lists.
Make sure we have a full set of blog parameters.

Go out and fill them in if necessary (and possible).
Merge pull request #11 from mdorman/merge

Get ready to start interacting with the server