docs: Document Timers in Node

[ryanmurakami]

This will track progress on a Documentation Overview of Timers in Node, as suggested in the Docs WG Roadmap for Q1 2016 (#70). Since an understanding of the Event Loop is pretty essential to giving context for timers, I'll be using nodejs/node#4936 as a branching off point to explain how timers work and best usages of the different API functions.

Here are some ideas I have for topics to cover:
Differences between intervalObject and timeoutObject and how they wrap Timer objects
Timer internals, like the linked list structure
... more to add

Any suggestions for topics are appreciated!

[stevemao]

related: #48 #34

[chrisdickinson]

Excellent! I've added this issue and your name to the roadmap. Thanks!

[ryanmurakami]

Opened a PR for the first draft: nodejs/nodejs.org#718

Also, not really sure if this is the right place to drop this guide? One of the other guides was created as a topic and dropped in node core. Let me know if this isn't the best place. Thanks!

[Fishrock123]

The PR landed at nodejs/node#6825 🎉

[Knighton910]

awesome 😄

[stevemao]

Can we close this?

[Knighton910]

the issue has landed, i don't see why not. Plus we need a pr to update the docs Roadmap on this

@stevemao do you want to make that PR or should i?

[stevemao]

#108

[ryanmurakami]

@lordKnighton @stevemao Thanks guys! Also, the event loop guide has been completed & merged as well by @techjeffharris. You can probably remove that line from the Roadmap also.

[Knighton910]

Cool 🎱 again though, awesome work.