CONTRIBUTORS: update Rietveld address for Kyle Lemons

R=golang-dev, bradfitz, r
CC=golang-dev
https://golang.org/cl/4634101

CONTRIBUTORS

@@ -141,7 +141,7 @@ Ken Thompson <ken@golang.org>
 Kevin Ballard <kevin@sb.org>
 Kirklin McDonald <kirklin.mcdonald@gmail.com>
 Kyle Consalus <consalus@gmail.com>
-Kyle Lemons <kyle@kylelemons.net> <etherealflaim@gmail.com>
+Kyle Lemons <kyle@kylelemons.net> <kevlar@google.com>
 Larry Hosken <lahosken@golang.org>
 Lorenzo Stoakes <lstoakes@gmail.com>
 Lucio De Re <lucio.dere@gmail.com>