Should accept `~` in paths in gpg.edn

[zilti]

It would be nice if bootlaces would support gpg certificate paths with the ~-character in them representing the home dir.

[micha]

I don't think we really want to have a special way to parse paths for this one file. I think we're probably better off sticking with the expected java paths across the board, no?

I looked around and couldn't really find anything in the way of performing shell expansion on paths in java. Seems like it would be pretty system specific. That would be confusing to people on different systems where the rules for ~ expansion are different. (For instance, what about ~username/...?)