Figure out how to deal with paths

[hroncok]

Especially in a containerized environment, we will have a lot of troubles, when client runs something as:

... --path /some/path

We'll need to figure out, how to deal with that.

[tradej]

For the Proof of Concept milestone, I would only document this as an issue that everything has to be done in the same $PWD.

Later, this should be solved with something like Docker volume containers or the like.