Footgun with relative paths and workdir option

[vorner]

The first time configuration is loaded, it is before switching the working directory (because the config contains the directory to switch to). The next time it is after the switch. If there's a relative path, it may point to something else or not exist, logging errors and not updating the config.

Possible improvements:

• Turn all the paths we know about to absolute on startup.
• Try loading the configuration once more just after switching the directory. This way errors manifest sooner (optimally even before we go to background), so the user is aware of them.

[vorner]

Turning all the ones from command line is done in v0.2.4. The ones from configuration wouldn't work ‒ the configuration may be reloaded later on.