try: add entrypoint and env-file options, fix genric options
TODO: bind mount the source into the build directly (see dockerfile buildkit)
added example folder with examples
refactored: install script much more robust, allows custom target
removedj volume command from dockerfile
* fix image name generation
* add logging directory and direct output to files there
removed linked mount in try script as btrfs does not create volume directories (bind mount only now)
move packages and init into separate directories to keep cache separate
fix some minor bugs