add ConfigurableRest proxy, which allows for more flexible URL building and custom configuration elements at proxy declaration time

add Config object for switching between production, play and local deployment modes without too much hassle; not well tested yet

add useStaticUrls flags to Config and proxy declarations, so that we can easily manage that both in dev and production

due to these, most of the load intelligence from controller.Main is totally removed, or at least moved into the Stores themselves.