CONTRIBUTORS: add Burcu Dogan's personal mail

Change-Id: I2bc92f6d33db44f96df4219e6144393d5150fe0f
Reviewed-on: https://go-review.googlesource.com/9785Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

CONTRIBUTORS

@@ -122,7 +122,7 @@ Brian G. Merrell <bgmerrell@gmail.com>
 Brian Gitonga Marete <marete@toshnix.com>
 Brian Ketelsen <bketelsen@gmail.com>
 Brian Slesinsky <skybrian@google.com>
-Burcu Dogan <jbd@google.com>
+Burcu Dogan <jbd@google.com> <burcujdogan@gmail.com>
 Caine Tighe <arctanofyourface@gmail.com>
 Caleb Spare <cespare@gmail.com>
 Carl Chatfield <carlchatfield@gmail.com>