Improve tool Docker file performance

[szschaler]

The docker files for the various tools (/static.xxx/Dockerfile) re-run Maven repeatedly. The way this is currently written, docker has no way to identify that parts of this build are redundant.

Instead, we should have just one staged-build Dockerfile for all tool services. This would start with a stage that builds all tools in one Maven call and then we would have separate stages for building each tool, copying the required information as and when. In the main docker-compose file, we then call the appropriate stage in this central Dockerfile instead of using a separate Dockerfile for each tool.

This way, Maven has to run once and the results can then be cached by Docker across all tools.