tools: add Node.js-specific ESLint rules

Add these rules:

* no-restricted-modules: See
http://eslint.org/docs/rules/no-restricted-modules. It has been
configured to prohibit the use of the deprecated `sys` and `_linklist`
modules.
* no-new-require: See http://eslint.org/docs/rules/no-new-require
* no-mixed-requires: http://eslint.org/docs/rules/no-mixed-requires

PR-URL: https://github.com/nodejs/node/pull/5320


Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Michaël Zasso <mic.besace@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>