Test in debian 9, ubuntu 14.04 and ubuntu 16.04

tests/dockerfiles/debian8/Dockerfile

@@ -1,6 +1,6 @@
 FROM debian:8
 
-WORKDIR /opt/
+RUN useradd -ms /bin/bash user
 
 RUN apt-get update && \
     apt-get install -y \
@@ -15,6 +15,7 @@ RUN apt-get update && \
 		wget \
 		&& rm -rf /var/lib/apt/lists/*
 
+WORKDIR /opt/
 COPY build /opt/build
 RUN  bash build