Steps doc update

src/views/steps/StepsDoc.vue

@@ -62,6 +62,12 @@ export default {
                             </tr>
 						</thead>
 						<tbody>
+                            <tr>
+                                <td>id</td>
+                                <td>string</td>
+                                <td>null</td>
+                                <td>Unique identifier of the element.</td>
+                            </tr>
                             <tr>
                                 <td>model</td>
                                 <td>array</td>
@@ -544,4 +550,4 @@ export default {
 			</TabPanel>
 		</TabView>
 	</div>
-</template>
+</template>