doc: add @shigeki and @mscdex to TC

voted in to Node.js Foundation TSC in meeting on 2015-06-17

Closes: https://github.com/nodejs/io.js/issues/1500
Closes: https://github.com/nodejs/io.js/issues/1501
PR-URL: https://github.com/nodejs/io.js/pull/2008
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>

README.md

@@ -319,10 +319,10 @@ information about the governance of the io.js project, see
 * **Nikolai Vavilov** <vvnicholas@gmail.com> ([@seishun](https://github.com/seishun))
 * **Nicu Micleușanu** <micnic90@gmail.com> ([@micnic](https://github.com/micnic))
 * **Aleksey Smolenchuk** <lxe@lxe.co> ([@lxe](https://github.com/lxe))
-* **Shigeki Ohtsu** <ohtsu@iij.ad.jp> ([@shigeki](https://github.com/shigeki))
+* **Shigeki Ohtsu** <ohtsu@iij.ad.jp> ([@shigeki](https://github.com/shigeki)) (Technical Committee)
 * **Sam Roberts** <vieuxtech@gmail.com> ([@sam-github](https://github.com/sam-github))
 * **Wyatt Preul** <wpreul@gmail.com> ([@geek](https://github.com/geek))
-* **Brian White** <mscdex@mscdex.net> ([@mscdex](https://github.com/mscdex))
+* **Brian White** <mscdex@mscdex.net> ([@mscdex](https://github.com/mscdex)) (Technical Committee)
 * **Christian Tellnes** <christian@tellnes.no> ([@tellnes](https://github.com/tellnes))
 * **Robert Kowalski** <rok@kowalski.gd> ([@robertkowalski](https://github.com/robertkowalski))
 * **Julian Duque** <julianduquej@gmail.com> ([@julianduque](https://github.com/julianduque))