Deprecate in favor of fb-watchman or chokidar

[aminya]

Summary

Atom's Pathwatcher is non-recursive, has issues (e.g slow Directory.getEntries), and lacks a maintainer to address these. We should probably deprecate this library and switch to one of the alternatives:

• fb-watchman: a native library that supports recursive watching. Being native means it is probably faster than Chokidar.
  fb-watchman

• Chokidar is used in Microsoft's Visual Studio Code, gulp, karma, PM2, browserify, webpack, BrowserSync, and many others.
  chokidar

Motivation

Fixing issues with directories and path watching

Describe alternatives you've considered

Improving Pathwatcher. However, due to the fact that no one actually maintains this repository, I think it is pointless to spend time improving the repository.

Two of my PRs and many of the other PRs are left untouched.
https://github.com/atom/node-pathwatcher/pulls?q=is%3Apr+is%3Aopen+sort%3Aupdated-desc

Additional context