Doesn't account for multiple users with same name

[micr0-dev]

If there are 2 people with the same name then bad things happen as the file with that name already exists. Either a discriminator must be given, Niko\ (2).txt. Or something else should be used for labeling the files (userID?)

~/go/bin/sigtop export-messages -k ~/passfile messages
sigtop: open Niko.txt: file exists