Added a couple of new websocket events

-lock_spacetime will lock the currently used spacetime so no other users can interact with it (prevents duplicate topics on a spacetime)
-unlock_spacetime unlocks the currently used spacetime so it may be interacted with again
-Lock triggers when a user clicks to create  new spacetime, and unlock when the modal is closed, either upon creation, or cancellation
Merge pull request #18 from jcerise/master

Added a couple of new websocket events