CLI's config.yml should not be deleted by updater

[bertfrees]

One solution would be to move config.yml out of the cli directory. Inside the cli directory is not such a good place anyway. For example, when packaged in a DEB a much better place would be /etc/opt/daisy-pipeline2-cli/. Or, on other *nix platforms, ~/.config/dp2/ is a common place as well.

The other solution is to make the updater only replace the cli/dp2 executable and not the whole cli directory. We do this by adding to the release descriptor entry the new attribute overwrite-path and set it to "false".