tools: replace closure-linter with eslint

PR-URL: https://github.com/iojs/io.js/pull/1539
Fixes: https://github.com/iojs/io.js/issues/1253


Reviewed-By: Jeremiah Senkpiel <fishrock123@rocketmail.com>
Reviewed-By: Trevor Norris <trev.norris@gmail.com>
Reviewed-By: Roman Reiss <me@silverwind.io>
Reviewed-By: Chris Dickinson <christopher.s.dickinson@gmail.com>
Reviewed-By: Johan Bergström <bugs@bergstroem.nu>
Reviewed-By: Fedor Indutny <fedor.indutny@gmail.com>