Earlier cli parsing and refactors

[Dlurak]

Previously the cli arguments in form of the Config struct was only parsed once the left mouse button is released. This is problematic for arguments like --version or --help, ferrishot would start but abort when the mouse button is released to show the version.

Now the Config is part of App and the cli arguments are parsed when iced inits App.

Also I did some refactors to have less/smaller if clauses in a match expression, no problem if you don't like those just let me know :)

[nik-rev]

Thanks!