Add version as label to Docker and adapt readme for new tags

Author: Morl99

Dockerfile

@@ -2,6 +2,9 @@ ARG POSTGRESQL_VERSION="13"
 FROM bitnami/postgresql:$POSTGRESQL_VERSION
 LABEL org.opencontainers.image.source="https://github.com/dbsystel/postgresql-partman-container"
 ARG PARTMAN_VERSION="v4.7.4"
+LABEL de.dbsystel.partman-version=$PARTMAN_VERSION
+ARG POSTGRESQL_VERSION
+LABEL de.dbsystel.postgres-version=$POSTGRESQL_VERSION
 ARG PARTMAN_CHECKSUM="28e4fdb83ecc16525959ae9593bfbfd077db429285f5f7d8e2468bfff6cbdbf2c81ace79a9ddeb4f00f51eb709163dbd713fe6b221a432ac2ff766f98d4cf8e4"
 USER root
 RUN install_packages wget gcc make build-essential

README.md

@@ -2,18 +2,27 @@
 
 This repo is meant to provide a Docker container that is based on the popular [bitnami/postgresql](https://hub.docker.com/r/bitnami/postgresql) container, that comes preinstalled with the [pg_partman](https://github.com/pgpartman/pg_partman) postgresql extension.
 
-It pushes a nightly latest image to ghcr.io
+It pushes a nightly latest image of all tag versions to [ghcr.io](https://github.com/orgs/dbsystel/packages/container/package/postgresql-partman)
 
 ## Usage
 
+```shell
+docker run ghcr.io/dbsystel/postgresql-partman
+docker run ghcr.io/dbsystel/postgresql-partman:{13,14,15,16}
+docker run ghcr.io/dbsystel/postgresql-partman:{13-4,14-4,15-4,16-4}
+docker run ghcr.io/dbsystel/postgresql-partman:{14-5,15-5,16-5}
 ```
-docker run ghcr.io/dbsystel/postgresql-partman:13
-docker run ghcr.io/dbsystel/postgresql-partman:14
-docker run ghcr.io/dbsystel/postgresql-partman:15
-docker run ghcr.io/dbsystel/postgresql-partman:16
-```
 
-The tags represent the postgresql major version. They will contain the latest available pg_partman version that was available at build time.
+The first part of the tag represent the postgresql major version, the second part represents the partman major version. If you leave out the second part, you will get the default version of partman as specified by this repository. Be aware, that this can change without notice.
+
+You can find out the actual versions used by looking at the labels of an image.
+
+`docker inspect ghcr.io/dbsystel/postgresql-partman:13`
+
+````
+  "de.dbsystel.partman-version" : "v4.7.4",
+  "de.dbsystel.postgres-version" : "13",
+````
 
 ## License