Support translations and using system language

[LeafHacker]

trafficstars

Instead of hard-coding UI strings, we should use a translation map that gets the value for the system language. The language could also be overridden by CLI arguments.

Users could then contribute translations via PRs or some other method.

[leijurv]

Oh dear

[leijurv]

this would be deceptive and problematic to have a multilingual installer for a english only piece of software

[LeafHacker]

True, but IMO that's Impact's problem not the installer's lol