Refactor nav component so that it only displays books for which we have data

app/components/scripture-nav-bar.js

@@ -17,29 +17,22 @@ export default class ScriptureNavBarComponent extends Component {
   constructor(...args) {
     super(...args);
     console.log(books);
-    this.books = this.availableBooks;
+    this.books = this.getBooks();
     // console.log(this.books);
   }
 
   // get only the books that we have backend data for
-  get
-  availableBooks()
+  async getBooks()
   {
-    return this.store.findAll('book').then(function(backendBooks) {
-      let available = [];
-      backendBooks.forEach(
-        value => {
-          let foundValue = books.find(function(book) {
-            return book['name'] == value.id
-          });
-          if(foundValue) {
-            available.push(foundValue);
-          }
-        });
-      return available;
-    }).then(function(response) {
-      console.log(response);
-      return response;
+    const results = await this.store.findAll('book');
+
+    this.books = results.map((book) => {
+      let foundValue = books.find(function(value) {
+        return value['name'] == book.id
+      });
+      if(foundValue) {
+        return foundValue;
+      }
     });
   }