Update backdrop.md

Update inconsistency between use of the word Overlay and Backdrop

docs/src/pages/components/backdrop/backdrop.md

@@ -1,13 +1,13 @@
 ---
-title: Overlay React component
+title: Backdrop React Component
 components: Backdrop
 ---
 
 # Backdrop
 
 <p class="description">The backdrop component is used to provide emphasis on a particular element or parts of it.</p>
 
-The overlay signals to the user of a state change within the application and can be used for creating loaders, dialogs and more.
+The backdrop signals to the user of a state change within the application and can be used for creating loaders, dialogs and more.
 In its simplest form, the backdrop component will add a dimmed layer over your application.
 
 {{"demo": "pages/components/backdrop/SimpleBackdrop.js"}}