Add comment on why it is necessary

.travis.yml

@@ -12,7 +12,7 @@ before_install:
 - vagrant/install_cluster.sh
 - vagrant/boot_cluster.sh
 - vagrant/create_topics.sh
-- go install -a -race regexp
+- go install -a -race regexp # Fix for go 1.2
 
 script:
 - go test -v -race ./...