Set branch to stable if no config file present

dzgui.sh

@@ -665,7 +665,10 @@ check_branch(){
 	upstream=$(curl -Ls "$version_url" | awk -F= '/^version=/ {print $2}')
 }
 check_version(){
-	source $config_file
+	if [[ ! -f $config_file ]]; then : else source $config_file; fi
+	if [[ -z $branch ]]; then
+		branch="stable"
+	fi
 	check_branch
 	if [[ $version == $upstream ]]; then
 		check_unmerged