multiplayer testing

[michaelpalumbo]

This is a large issue that will get broken into several issues

goal: run two non-vr sessions of mischmasch. use keys to add an op in one app and see it replicated in the other.

steps:

• [x] startup flag for non-VR session
• [x] check that it can be run twice simultaneously
• [x] if it can't be run twice on same machine, can the 2nd be run on osx?
• [x] ~add keyboard input for spawning a new op~ cut for now, for now can run one session in vr, the other WASD, and spawn using VR
• [x] implement automerge sync protocol see #237
• [ ] ?