[Docker] Make sure python3 and perl are installed

docker/setup_os.Ubuntu-16.04.sh

@@ -20,7 +20,7 @@ set -e
 apt-get update -y
 
 apt-get install -y libgraphviz-perl libchart-gnuplot-perl
-apt-get install -y --no-install-recommends curl perl-doc \
+apt-get install -y --no-install-recommends curl python3 perl perl-doc \
                    sqlite3 libdbd-sqlite3-perl postgresql-client libdbd-pg-perl mysql-client libdbd-mysql-perl libdbi-perl \
                    libcapture-tiny-perl libdatetime-perl libhtml-parser-perl libjson-perl libemail-mime-perl libemail-sender-perl libemail-simple-perl libproc-daemon-perl \
                    libtest-exception-perl libtest-simple-perl libtest-warn-perl libtest-warnings-perl libtest-file-contents-perl libtest-perl-critic-perl libtest-fatal-perl \