Made player simulation non-blocking.
Clean up inventory.
Clean up controls.js, make keyboard layout easily settable with localStorage flag.
Made inventory items activatable again.
Entirely server-side prediction is mostly working now.
Server uses client frametime for calculations now. This entails trusting the client (they could just lie about their frametime), but we'll fix that soon enough.
Cleanup. We no longer trust the client's FrameTime, but we still trust their Timestamp. Somehow we have to normallize all of the incoming timestamps to one clock. Hmmm.