Remove the MethodHandler, the Mux router calls the NotFoundHandler if
the method isn't set. So MethodHandler doesn't get called for incorrect
methods allowing me to send the proper response.
Add setup script to call before starting a server.

Refactor some Redis data, make it more consistent. Namespace
"users:<user>:device:<device>" changed to "users:<user>:devices:<device>"
Move all API documentation to README