Update readme with deprecation notes

Author: Martyn Hoyer

Diff for: readme.md

@@ -1,41 +1,44 @@
 # storybook-styled-components
 
-![Theme Picker Animation](./docs/theme-picker.gif)
+**DEPRECATED!**
+
+This plugin has issues when used with Storybook v5 and beyond, and there's a better option available at:
+https://github.com/echoulen/storybook-addon-styled-component-theme
 
-### Switch between themes and see how your components react
+![Theme Picker Animation](./docs/theme-picker.gif)
 
+_Switch between themes and see how your components react_
 
 ## Set It Up
 
 inside your storybook addons, register the `storybook-styled-components`:
 
 ```javascript
 // addons.js
-import 'storybook-styled-components/register'
+import "storybook-styled-components/register";
 ```
 
 In your config.js, define your theme configuration and pass it in to the `addDecorator` function
 
-
 ```javascript
 // config.js
-import { configure, addDecorator } from '@storybook/react'
-import { withThemes } from 'storybook-styled-components'
+import { configure, addDecorator } from "@storybook/react";
+import { withThemes } from "storybook-styled-components";
 
 // then import your themes
-import firstTheme from './src/themes/first'
-import secondTheme from './src/themes/second'
+import firstTheme from "./src/themes/first";
+import secondTheme from "./src/themes/second";
 
 const themes = {
-  'First Theme': firstTheme,
-  'Second Theme': secondTheme,
-}
+  "First Theme": firstTheme,
+  "Second Theme": secondTheme
+};
 
 // now add the decorator
-addDecorator(withThemes(themes))
+addDecorator(withThemes(themes));
 // done!
 ```
 
-#### This is still a Work In Progress ... Feedback welcomed
+**This is still a Work In Progress ... Feedback welcomed**
 
-# [Read The License](./license.md)
+[Read The License](./license.md)