Simplify collection events
Prevent leaks when switching collection
Naive implementation of reaching dependencies without global listeners
Improve global dependecies
Make sure manual resolution of async event works as intended
Send in old value to change events
Fix case where dependent property is reassigned
Handle changing collections
Fix some failures due to new global dependencies
Put behaviour on event itself
Remove useless if statement
Fix some values not being closed over properly
Fix some specs
Don't choke on invalid dependencies
Test changed: true behaviour
Rebind is unnecessary
Better tests for `changed` option