Add "mirrored" sparks class using http gem to enable discussion.

Here's what I currently have for sparks using the http gem library. I'm not sure if this is the way you want to go @indirect. If you don't want to require the use of the http gem (instead of net-http-persistent) I could go with something more like an adapter.

Obviously, this isn't ready to merge in as is, only for discussion.

I would like to consider making a class for Room to encapsulate some of the id-related stuff, help clean up the interface a touch. But, I really like the simplicity, so I wouldn't push that either.