Remove scoped styles & add caveat comment about Purge

Author: chasegiunta

src/components/HelloWorld.vue

@@ -44,7 +44,8 @@ export default {
 </script>
 
 <!-- Add "scoped" attribute to limit CSS to this component only -->
-<style scoped>
+<!-- @apply classes may be incorrectly purged if "scoped" is present -->
+<style>
 .hello {
   @apply text-white;
 }