Merge branch 'postgres_13_support' into 'master'

added support of Postgres 13 in Dockerfile 
based on it can be build extended image based on Postgres 13
```
sudo docker build --build-arg PG_SERVER_VERSION=13 -t postgres-extended-13 .
```

For PostgreSQL in comparison with Postgres 11 and 12 we don't have following extensions:

1. removed in base image of Postgres 13

* hll
* timetravel
* topn

2. don't support 13 yet (expect soon):

* citus
* hypopg
* pg_auth_mon
* pg_hint_plan
* powa
* timescaledb

related https://gitlab.com/postgres-ai/custom-images/-/issues/2

See merge request postgres-ai/custom-images!17

Author: agneum

extended/Dockerfile

@@ -11,40 +11,48 @@ ENV CITUS_VERSION=9.4
 RUN apt-get clean && rm -rf /var/lib/apt/lists/partial \
     && apt-get update -o Acquire::CompressionTypes::Order::=gz \
     && apt-get install --no-install-recommends -y wget make gcc unzip sudo git \
-       curl libc6-dev apt-transport-https ca-certificates pgxnclient \
+       curl libc6-dev apt-transport-https ca-certificates pgxnclient bc \
        build-essential libevent-dev libssl-dev krb5-multidev \
     && apt-get install --no-install-recommends -y \
        postgresql-server-dev-${PG_SERVER_VERSION} \
     && apt-get install --no-install-recommends -y \
        postgresql-${PG_SERVER_VERSION}-repack \
-    && apt-get install --no-install-recommends -y \
-       postgresql-${PG_SERVER_VERSION}-hypopg \
-    && apt-get install --no-install-recommends -y \
-       postgresql-${PG_SERVER_VERSION}-hypopg-dbgsym \
-    # pg_hint_plan extension (dots are to be skipped here, e.g., "9.6" -> "96")
-    && export PG_PLAN_HINT_VERSION=$(echo $PG_SERVER_VERSION | sed 's/\.//') \
-      && wget --quiet -O /tmp/pg_hint_plan.zip \
+    # extensions supported in PostgreSQL 12 and below 
+    # bc is used to manage PostgreSQL versions with dot like 9.6
+    && if [ $(echo "$PG_SERVER_VERSION < 13" | /usr/bin/bc) = "1" ]; then \
+     # hypopg
+     apt-get install --no-install-recommends -y \
+         postgresql-${PG_SERVER_VERSION}-hypopg \
+     && apt-get install --no-install-recommends -y \
+         postgresql-${PG_SERVER_VERSION}-hypopg-dbgsym \
+     # pg_hint_plan extension (dots are to be skipped here, e.g., "9.6" -> "96")
+     && export PG_PLAN_HINT_VERSION=$(echo $PG_SERVER_VERSION | sed 's/\.//') \
+       && wget --quiet -O /tmp/pg_hint_plan.zip \
          https://github.com/ossc-db/pg_hint_plan/archive/PG${PG_PLAN_HINT_VERSION}.zip \
-      && unzip /tmp/pg_hint_plan.zip -d /tmp \
+       && unzip /tmp/pg_hint_plan.zip -d /tmp \
          && cd /tmp/pg_hint_plan-PG${PG_PLAN_HINT_VERSION} \
-      && make && make install \
-   # timescaledb extension
-   && echo 'deb https://packagecloud.io/timescale/timescaledb/debian/' \
-      $(env -i bash -c '. /etc/os-release; echo ${VERSION_CODENAME}') \
-      'main' > /etc/apt/sources.list.d/timescaledb.list \
-      && wget --quiet -O - \
+         && make && make install \
+     # timescaledb extension
+     && echo 'deb https://packagecloud.io/timescale/timescaledb/debian/' \
+       $(env -i bash -c '. /etc/os-release; echo ${VERSION_CODENAME}') \
+       'main' > /etc/apt/sources.list.d/timescaledb.list \
+     && wget --quiet -O - \
          https://packagecloud.io/timescale/timescaledb/gpgkey | sudo apt-key add - \
-      && apt-get update \
-      && apt-get install -y timescaledb-postgresql-${PG_SERVER_VERSION} \
+       && apt-get update \
+       && apt-get install -y timescaledb-postgresql-${PG_SERVER_VERSION} \
+     # powa extension
+     && apt-get install postgresql-${PG_SERVER_VERSION}-powa \
+     # pg_auth_mon extension
+     && git clone https://github.com/RafiaSabih/pg_auth_mon.git \
+     && cd pg_auth_mon && USE_PGXS=1 make && USE_PGXS=1 make install; \
+   fi \
    # citus extension; only Postgres 11 and 12 are supported by citus
    && if [ "${PG_SERVER_VERSION}" = "12" ] || [ "${PG_SERVER_VERSION}" = "11" ]; then \
       curl -s https://install.citusdata.com/community/deb.sh | bash \
       && apt-get install -y postgresql-${PG_SERVER_VERSION}-citus-${CITUS_VERSION} \
          postgresql-${PG_SERVER_VERSION}-hll=2.14.citus-1 \
          postgresql-${PG_SERVER_VERSION}-topn=2.3.0; \
       fi \
-   # powa extension
-   && apt-get install postgresql-${PG_SERVER_VERSION}-powa \
    # pg_timetable extension
    && wget https://github.com/cybertec-postgresql/pg_timetable/releases/download/v2.3.0/pg_timetable_2.3.0_Linux_x86_64.deb \
      && dpkg -i pg_timetable_2.3.0_Linux_x86_64.deb \
@@ -66,9 +74,6 @@ RUN apt-get clean && rm -rf /var/lib/apt/lists/partial \
      && USE_PGXS=1 make && USE_PGXS=1 make install \
    # pgextwlist extension
    && apt-get install postgresql-${PG_SERVER_VERSION}-pgextwlist \
-   # pg_auth_mon extension
-   && git clone https://github.com/RafiaSabih/pg_auth_mon.git \
-     && cd pg_auth_mon && USE_PGXS=1 make && USE_PGXS=1 make install \
    # set_user extension
    && git clone https://github.com/pgaudit/set_user.git \
      && cd set_user && make USE_PGXS=1 && make USE_PGXS=1 install \