Implementing user-hub edge list.
User-Hub edge list, second pass.
User-Hub edge list, third pass.
User-Hub edge-list, fourth pass.
Renaming to edge map, create indexes in the db.
Redoing edge from users to conn instead.
Start implementing edge map for user-hub.
Merge branch 'redesign_hub_logic'

Conflicts:
	conn.go
	hub.go
Merge branch 'master' of https://github.com/ygabo/chatgo