Fix tb-postgres docker image. Update postgreSQL version to 11

msa/tb/docker-postgres/Dockerfile

@@ -17,7 +17,11 @@
 FROM thingsboard/openjdk8
 
 RUN apt-get update
-RUN apt-get install -y postgresql postgresql-contrib
+RUN apt-get install -y curl
+RUN echo 'deb http://apt.postgresql.org/pub/repos/apt/ stretch-pgdg main' | tee --append /etc/apt/sources.list.d/pgdg.list > /dev/null
+RUN curl -L https://www.postgresql.org/media/keys/ACCC4CF8.asc | apt-key add -
+RUN apt-get update
+RUN apt-get install -y postgresql-11
 RUN update-rc.d postgresql disable
 
 RUN mkdir -p /var/log/postgres

msa/tb/docker-postgres/start-db.sh

@@ -17,13 +17,15 @@
 
 firstlaunch=${DATA_FOLDER}/.firstlaunch
 
+export PG_CTL=$(find /usr/lib/postgresql/ -name pg_ctl)
+
 if [ ! -d ${PGDATA} ]; then
     mkdir -p ${PGDATA}
     chown -R postgres:postgres ${PGDATA}
-    su postgres -c '/usr/lib/postgresql/10/bin/pg_ctl initdb -U postgres'
+    su postgres -c '${PG_CTL} initdb -U postgres'
 fi
 
-su postgres -c '/usr/lib/postgresql/10/bin/pg_ctl -l /var/log/postgres/postgres.log -w start'
+su postgres -c '${PG_CTL} -l /var/log/postgres/postgres.log -w start'
 
 if [ ! -f ${firstlaunch} ]; then
     su postgres -c 'psql -U postgres -d postgres -c "CREATE DATABASE thingsboard"'

msa/tb/docker-postgres/stop-db.sh

@@ -15,4 +15,6 @@
 # limitations under the License.
 #
 
-su postgres -c '/usr/lib/postgresql/10/bin/pg_ctl stop'
+export PG_CTL=$(find /usr/lib/postgresql/ -name pg_ctl)
+
+su postgres -c '${PG_CTL} stop'