[ADF-1549] Added doc files for Tasklist library (#2350)

docs/checklist.component.md

@@ -0,0 +1,32 @@
+# Activiti Checklist Component
+
+Shows the checklist task functionality.
+
+<!-- markdown-toc start - Don't edit this section.  npm run toc to generate it-->
+
+<!-- toc -->
+
+- [Basic Usage](#basic-usage)
+  * [Properties](#properties)
+
+<!-- tocstop -->
+
+<!-- markdown-toc end -->
+
+## Basic Usage
+
+```html
+<adf-checklist 
+    [readOnly]="false" 
+    [taskId]="taskId" 
+    [assignee]="taskAssignee.id" 
+</adf-checklist>
+```
+
+### Properties
+
+| Name | Type | Description |
+| --- | --- | --- |
+| taskId | string | (**required**) The id of the parent task which sub tasks are attached on. |
+| readOnlyForm | boolean | Toggle readonly state of the form. Enforces all form widgets render readonly if enabled. |
+| assignee | string | (**required**) The assignee id where the subtasks are assigned to. |