devtools/prodimage: create

We start having the need to have our own production image instead ofjust
a bare Ubuntu image. For instance, octorpki will need rync and TLS CA
bundles.

Change-Id: Ia8d9604ae8c320f858cfe8a2dc21ddcc321017ff
diff --git a/devtools/prodimage/Dockerfile b/devtools/prodimage/Dockerfile
new file mode 100644
index 0000000..85a0e50
--- /dev/null
+++ b/devtools/prodimage/Dockerfile
@@ -0,0 +1,9 @@
+FROM ubuntu:bionic-20190515
+
+RUN set -e -x ;\
+    export DEBIAN_FRONTEND=noninteractive ;\
+    apt-get -y update ;\
+    apt-get -y install \
+        ca-certificates \
+        rsync ;\
+    rm -rf /var/lib/apt/lists