move image updates into the base layer

Author: alee

Dockerfile

@@ -1,11 +1,12 @@
 # base CoMSES Dockerfile
 FROM phusion/baseimage:0.9.22
 LABEL maintainer="Allen Lee <allen.lee@asu.edu>"
+
+RUN apt-get update && apt-get upgrade -y -o Dpkg::Options::="--force-confold"
 
 ONBUILD ENV PYTHONUNBUFFERED=1 \
             COMSES_UID=2718 \
             COMSES_USER=comses \
             LANG=C.UTF-8 \
             LC_ALL=C.UTF-8
-ONBUILD RUN apt-get update && apt-get upgrade -y -o Dpkg::Options::="--force-confold" \
-    && useradd -m --uid $COMSES_UID $COMSES_USER
+ONBUILD RUN useradd -m --uid $COMSES_UID $COMSES_USER