Support for ~/ in output dir

[phuhl]

It seems that when using ~/ in the output dir path, no screenshot is saved and no error message is produced.

It would be good to be able to use the ~ shortcut for the home directory of the user.

[gabm]

yeah, there is currently no path expansion.. sure there is no message? if there is a positive message, maybe you have a file on your hdd somewhere that starts with ~/?

[phuhl]

Ok, apparently there was an error message, no idea why I did'nt see it last time

[gabm]

okay.. nevertheless: path expansion might be nice

[gabm]

here are a number of alternatives: https://stackoverflow.com/questions/54267608/expand-tilde-in-rust-path-idiomatically

[xlucn]

Shell expand is a good option. That allows even more customization, like $HOME.