separate out the storage controller into http://npmjs.org/package/remotestorage-server

as also discussed in https://groups.google.com/d/msg/unhosted/s-jimKXlUXE/vrtxim7kTukJ - since https://github.com/remotestorage/starter-kit and https://github.com/remotestorage/remotestorage.js/tree/integration-tests also both implement the same business logic of the storage controller, but have different requirements for the actual store and web interface, i put this common part into https://github.com/remotestorage/remotestorage-server

i didn't clean up the parts of the code yet that are now unused (mainly `/lib/controllers/storage`), just wanted to ask you for some feedback first!

cheers,
Michiel