Use TZ Dockerfile argument to set the time zone. For...

Use TZ Dockerfile argument to set the time zone.  For https://github.com/dtu-compute/dtu-enote/issues/62

Dockerfile

 FROM fedora:23
 
-RUN ln -sf /usr/share/zoneinfo/Europe/Copenhagen /etc/localtime && \
-    dnf -y update && \ 
+LABEL github="https://github.com/dtu-compute/dtu-enote-mongodb"
+LABEL version="2018"
+LABEL description="This Dockerfile builds the container \
+MongoDB that serves ShareLatex."
+
+ARG TZ=Europe/Copenhagen
+
+# Set timezone
+RUN cp /usr/share/zoneinfo/$TZ /etc/localtime
+RUN bash -l -c 'echo "${TZ}" > /etc/timezone'
+
+RUN dnf -y update && \ 
     dnf -y install mongodb mongodb-server mongo-tools pwgen iproute && \
     dnf clean all