add option "monitor" to dunstrc

dunst.c

@@ -1017,6 +1017,8 @@ dunst_ini_handle(void *user_data, const char *section,
                         history_key_string = dunst_ini_get_string(value);
                 else if (strcmp(name, "idle_threshold") == 0)
                         idle_threshold = atoi(value);
+                else if (strcmp(name, "monitor") == 0)
+                        scr.scr = atoi(value);
                 else if (strcmp(name, "geometry") == 0) {
                         geom = dunst_ini_get_string(value);
                         geometry.mask = XParseGeometry(geom,

dunstrc

@@ -42,6 +42,9 @@
     # Set to 0 to disable.
     idle_threshold = 120
 
+    # Which monitor should the notifications be displayed one
+    monitor = 0
+
 [urgency_low]
     # IMPORTANT: colors have to be defined in quotation marks.
     # Otherwise the '#' and following  would be interpreted as a comment.