[release-branch.go1] CONTRIBUTORS: add Colby Ranger (Google CLA)

««« backport 4875dfefc730
CONTRIBUTORS: add Colby Ranger (Google CLA)

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/6037052
»»»

CONTRIBUTORS

@@ -85,6 +85,7 @@ Christopher Nielsen <m4dh4tt3r@gmail.com>
 Christopher Redden <christopher.redden@gmail.com>
 Christopher Wedgwood <cw@f00f.org>
 Clement Skau <clementskau@gmail.com>
+Colby Ranger <cranger@google.com>
 Conrad Meyer <cemeyer@cs.washington.edu>
 Corey Thomasson <cthom.lists@gmail.com>
 Damian Gryski <dgryski@gmail.com>