blog: add author name to errors blog post

Change-Id: Ic440bb4bff6a1efd63820a2981931913cb5f1f84
Reviewed-on: https://go-review.googlesource.com/2710
Reviewed-by: Andrew Gerrand <adg@golang.org>
diff --git a/content/errors-are-values.article b/content/errors-are-values.article
index fa5fedf..eff779e 100644
--- a/content/errors-are-values.article
+++ b/content/errors-are-values.article
@@ -1,6 +1,8 @@
 Errors are values
 12 Jan 2015
 
+Rob Pike
+
 * Introduction
 
 A common point of discussion among Go programmers,