Add image autocleaner

[lebedevilya]

This option is created in order to clean old images after update

[djmaze]

Looks good to me! Although personally I'd rather just use docker system prune.

It would be good to have an explaining sentence in the README, like for the other options. Can you add that? Otherwise I will do it.

Also, I will probably squash your commits into one.

[lebedevilya]

Looks good to me! Although personally I'd rather just use docker system prune.

It would be good to have an explaining sentence in the README, like for the other options. Can you add that? Otherwise I will do it.

Also, I will probably squash your commits into one.

Good day! I added explanation to README; squashing commits seems like a good idea. About docker system prune - at first we decided to go that way, but we found that unsafe because you might unintentionally delete something you wanted to keep. This script ensure you clean only images of this exact service, which was updated, and no others will be affected.

[djmaze]

Thanks!