Add 'never' constructor
Create a better Subscriber type, more like Rx
Add an Event type
Shit's getting real
Add an empty disposable type
Added CompositeDisposable
Fix subscribers not honoring disposal
Refactor signals to use real events
Update Subject.hs
Update tests
Merge branch 'better-subscribers'
Added fromFoldable
Zip that shit
Added materialize/dematerialize
Add custom background schedulers
Delint some things
Rename 'subject' to 'newSubject'
Add 'start' to create a signal on a scheduler
Add hLineSignal for getting a Signal from a Handle
Perform composite disposal outside of any MVars

This ensures that recursively disposing of a composite disposable won't deadlock.