Add missing Dockerfile

apt-publisher/Dockerfile

+FROM ubuntu:16.04
+
+MAINTAINER Ray Burgemeestre
+
+RUN apt-get update && \
+    apt install -y sudo wget gnupg2 \
+                   apache2 dpkg-dev dpkg-sig \
+                   apt-utils && \
+    \
+    mkdir -p /repo && \
+    mkdir -p ~/.gnupg && \
+    rm -rf /var/lib/apt/lists/*
+
+CMD "/bin/bash"