small naming changes
more perf & refactoring

- reduce closures
- isolate necessary de-optimizations to small functions
- reduce overhead of internals usage by adding the ability for
  _internals_ to subscribe to other promises without the expense of
`then`
- fulfillment with no subscribers need not attempt to queue and
  broadcast to subscribers. The Act of subscribing queues, schedules and
flushes the micro task queue.
Merge pull request #246 from stefanpenner/more-opts

More opts