Update README.md for Slideovers (#48)

README.md

@@ -46,12 +46,13 @@ const context = require.context("controllers", true, /.js$/);
 application.load(definitionsFromContext(context));
 
 // Import and register all TailwindCSS Components
-import { Dropdown, Modal, Tabs, Popover, Toggle } from "tailwindcss-stimulus-components"
+import { Dropdown, Modal, Tabs, Popover, Toggle, Slideover } from "tailwindcss-stimulus-components"
 application.register('dropdown', Dropdown)
 application.register('modal', Modal)
 application.register('tabs', Tabs)
 application.register('popover', Popover)
 application.register('toggle', Toggle)
+application.register('slideover', Slideover)
 ```
 
 This will start StimulusJS and load any controllers that you have