Document how to add middleware with express apps using moonboots.

[latentflip]

Figured out my file upload issue: express middleware has to be added before routes are defined. I was adding middleware after initializing moonboots, and I hadn't clocked that moonboots would be adding a route handler, which means I can't add middleware after moonboots.

[wraithgar]

Moonboots doesn't add a route handler anymore, there is moonboots-hapi and soon to be moonboots-express, and they are documented in the readme.