client->server presence code working
Added end-to-end presence support
Presence data is raw (not in .data key)
Purged other users session data when they go offline
Presence is scoped to contexts
transformCursor -> transformSelection
added setPresenceProperty
Collapsed single value ranges
Added setPresenceProperty to context
Fixed a couple bugs
Fixed buggy transform fixing code in _setType
Fixed typo
Tweaked presence events
cleanup: Remove all trailing whitespace.
cleanup: Rename _this to self.
Merge pull request #307 from Dignifiedquire/presence_fix

[presence] Cleanup
merge presence