chore(*): bump go1.7.4

Author: adamreese

circle.yml

@@ -3,7 +3,7 @@ machine:
     - curl -sSL https://s3.amazonaws.com/circle-downloads/install-circleci-docker.sh | bash -s -- 1.10.0
 
   environment:
-    GOVERSION: "1.7.3"
+    GOVERSION: "1.7.4"
     GOPATH:  "${HOME}/.go_workspace"
     WORKDIR: "${GOPATH}/src/k8s.io/helm"
     PROJECT_NAME: "kubernetes-helm"