gnupload touchups. * lib/gnupload (conffile): New variable. Use throughout. (dry_run): Use `false' and `:' values. Show, don't execute, gpg signing commands upon --dry-run. (usage): Typo and formatting fixes. Mention that commands are applied in order. (argument loop): Factorize a bit, fix quoting. (dprint, mkdirective, mksymlink, upload): Formatting and portability fixes. Signed-off-by: Ralf Wildenhues <Ralf.Wildenhues@gmx.de>