async_hooks: initial async_hooks implementation

Fill this commit messsage with more details about the change once all
changes are rebased.

* Add lib/async_hooks.js

* Add JS methods to AsyncWrap for handling the async id stack

* Introduce AsyncReset() so that JS functions can reset the id and again
  trigger the init hooks, allow AsyncWrap::Reset() to be called from JS
  via asyncReset().

* Add env variable to test additional things in test/common.js

PR-URL: https://github.com/nodejs/node/pull/12892
Ref: https://github.com/nodejs/node/pull/11883
Ref: https://github.com/nodejs/node/pull/8531


Reviewed-By: Andreas Madsen <amwebdk@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Sam Roberts <vieuxtech@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Jeremiah Senkpiel <fishrock123@rocketmail.com>