Include OS version into tag

[christiangalsterer]

In addition to the name of OS/variant and the Java version it would be good to also include the OS version in the tag name.

For more regulated environment it makes tracing, inventory and audits more easy.

Example:
8u131-jre-alpine would become 8u131-jre-alpine_3.6.

If you are considering this as useful, please let me know about the format and could provide a PR.