Make printed errors show defined messages

[bermudalocket]

Printing the error's localized description (before):

The operation couldn’t be completed. (sfsymbols.ArgumentParserError error 5.)
Program ended with exit code: 0

Printing the error object itself (after):

fontLocationString("Unable to locate suitable SF Symbols font")
Program ended with exit code: 0

[MoOx]

@davedelong this would help to somehow close #23 as the error would become more obvious :)

[malhal]

Please merge this