Add ability to tag docker images with their used core version

Description

To avoid deployments where one has to manually check the used core versions of all the images we should have tags for the images by the used core version.

Explanation

A typical deployment would look something like this:

• App - Version U
• Backend - Version V
• Connector A - Version W
• Connector B - Version X
• API - Version Y

Instead this could an shoud be:

• App - Core version Z
• Backend - Core version Z
• Connector A - Core version Z
• Connector B - Core version Z
• API - Core version Z

Dependencies, issues to be resolved beforehand

This should probably be consolidated with #19 (moved)?

cc: @All