Initial PubNub setup

- connect and subscribe to channel with UUID and state
- Add players on presence join
adding missing notifier
Merge branch 'master' into pubnub
some join and movement events
PubNub multiplayer

- adds players/avatars on pubnub join
- removes players/avatars on pubnub leave
- transmits position and avatar orientation

TODO:
- remove players on PN timeout
- only pan camera around current_player
- fix Trailblazer with multiple players
add existing players when joining
only pan map for current player
don't clean up trails so drawing doesn't get weird.
fixing left-facing orientation of avatar
adding Map.svg
basic chat stuff
Merge pull request #5 from cremalab/pubnub

Pubnub