tools: replace obsolete ESLint rules

Now that we are using ESLint 2, replace ESLint 1 rules with their ESLint
2 equivalents.

PR-URL: https://github.com/nodejs/node/pull/5214


Reviewed-By: Michaël Zasso <mic.besace@gmail.com>
Reviewed-By: jbergstroem - Johan Bergström <bugs@bergstroem.nu>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Roman Reiss <me@silverwind.io>
Reviewed-By: Myles Borins <myles.borins@gmail.com>