Synchronize units on control and settings pages.

src/js/app.js

@@ -417,7 +417,8 @@ module.exports = new Vue({
             delete settings.tool["tool-type"];
 
             this.config["selected-tool-settings"][selected_tool] = settings;
-
+            this.display_units = this.config.settings["units"];
+  
             try {
                 await api.put("config/save", this.config);
                 this.modified = false;

src/js/control-view.js

@@ -91,7 +91,9 @@ module.exports = {
                 return this.$root.display_units;
             },
             set: function(value) {
+                this.config.settings.units = value;
                 this.$root.display_units = value;
+                this.$dispatch("config-changed");
             }
         },