[CORD-2874]
Use newer alpine in provisioner container as a way to update to ansible v2.4

Change-Id: I5bda28df544377f5f8090dd6613c8eed328d9a11
diff --git a/provisioner/Dockerfile.provisioner b/provisioner/Dockerfile.provisioner
index cfc8850..a0ad638 100644
--- a/provisioner/Dockerfile.provisioner
+++ b/provisioner/Dockerfile.provisioner
@@ -20,7 +20,7 @@
 ADD . /go/src/gerrit.opencord.org/maas/cord-provisioner
 RUN go build -o /build/entry-point gerrit.opencord.org/maas/cord-provisioner
 
-FROM alpine:3.6
+FROM alpine:3.7
 MAINTAINER Open Networking Laboratory <info@onlab.us>
 
 # Base image information borrowed by official golang wheezy Dockerfile