Fix no password prompt. Fixes #2408 (#2409)

Author: tdulcet

setup/firstuser.sh

@@ -48,7 +48,7 @@ if [ -z "$(management/cli.py user)" ]; then
 	fi
 
 	# Create the user's mail account. This will ask for a password if none was given above.
-	management/cli.py user add "$EMAIL_ADDR" "${EMAIL_PW:-}"
+	management/cli.py user add "$EMAIL_ADDR" ${EMAIL_PW:+"$EMAIL_PW"}
 
 	# Make it an admin.
 	hide_output management/cli.py user make-admin "$EMAIL_ADDR"