Allow adding items to be disabled for list widget (#1102)

website/site/content/docs/widgets/list.md

@@ -13,6 +13,7 @@ The list widget allows you to create a repeatable item in the UI which saves as
 - **Data type:** list of widget values
 - **Options:**
   - `default`: if `fields` is specified, declare defaults on the child widgets; if not, you may specify a list of strings to populate the text field
+  - `allow_add`: if added and labeled `false`, button to add additional widgets disapears
   - `field`: a single widget field to be repeated
   - `fields`: a nested list of multiple widget fields to be included in each repeatable iteration
 - **Example** (`field`/`fields` not specified):
@@ -24,6 +25,16 @@ The list widget allows you to create a repeatable item in the UI which saves as
     default: ["news"]
   ```
 
+- **Example** (`allow_add` marked `false`):
+
+  ```yaml
+  - label: "Tags"
+    name: "tags"
+    widget: "list"
+    allow_add: false
+    default: ["news"]
+  ```
+
 - **Example** (with `field`):
 
   ```yaml