CONTRIBUTORS: code review email for Jamie Gennis

R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/5646051

CONTRIBUTORS

@@ -134,7 +134,7 @@ James Meneghello <rawrz0r@gmail.com>
 James P. Cooper <jamespcooper@gmail.com>
 James Toy <nil@opensesame.st>
 James Whitehead <jnwhiteh@gmail.com>
-Jamie Gennis <jgennis@google.com>
+Jamie Gennis <jgennis@google.com> <jgennis@gmail.com>
 Jan H. Hosang <jan.hosang@gmail.com>
 Jan Mercl <befelemepeseveze@gmail.com>
 Jan Newmarch <jan.newmarch@gmail.com>