Engine selection params conflicts with file paths

[soimort]

I did not take that into consideration so much when I introduced the shortcut parameters (/engine) for engine selection, and now this becomes an issue for me:

$ trans /home/soimort/Documents/foobar
[ERROR] Translator not found: home/soimort/Documents/foobar
        Run '-list-engines / -S' to see a list of available engines.

[soimort]

You need to use a file URI scheme:

$  trans file:///home/soimort/Documents/foobar