doc: add ronkorving to collaborators

Reviewed-By: Evan Lucas <evanlucas@me.com>
Reviewed-By: Johan Bergström <bugs@bergstroem.nu>
Reviewed-By: Rich Trott <rtrott@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/6385

README.md

@@ -197,6 +197,7 @@ information about the governance of the Node.js project, see
 * [rmg](https://github.com/rmg) - **Ryan Graham** <r.m.graham@gmail.com>
 * [robertkowalski](https://github.com/robertkowalski) - **Robert Kowalski** <rok@kowalski.gd>
 * [romankl](https://github.com/romankl) - **Roman Klauke** <romaaan.git@gmail.com>
+* [ronkorving](https://github.com/ronkorving) - **Ron Korving** <ron@ronkorving.nl>
 * [saghul](https://github.com/saghul) - **Saúl Ibarra Corretgé** <saghul@gmail.com>
 * [sam-github](https://github.com/sam-github) - **Sam Roberts** <vieuxtech@gmail.com>
 * [santigimeno](https://github.com/santigimeno) - **Santiago Gimeno** <santiago.gimeno@gmail.com>