Update the measure tool how to to include initialUnits

docs/howto/configure-measure-tool.md

@@ -27,3 +27,17 @@ Here's the example from the demo:
   * `ch` for chains.
   * `a` for acres.
   * `h` for hectares.
+
+## Example of setting the default units to meters
+
+The code below will set the default the measurement units to meters instead of feet.
+
+```javascript
+    app.add(gm3.components.ServiceManager, 'service-tab', {
+        services: true,
+        measureToolOptions: {
+            pointProjections: point_projections,
+            initialUnits: 'm'
+        }
+    });
+```

examples/desktop/app.js

@@ -152,7 +152,8 @@ app.loadMapbook({url: 'mapbook.xml'}).then(function() {
     app.add(gm3.components.ServiceManager, 'service-tab', {
         services: true,
         measureToolOptions: {
-            pointProjections: point_projections
+            pointProjections: point_projections,
+            initialUnits: 'mi'
         }
     });