Fix BookReplaceCommand

src/de/steamwar/tutorial/commands/BookReplaceCommand.java

@@ -42,7 +42,7 @@ public class BookReplaceCommand extends SWCommand {
         List<String> stringList = bookMeta.getPages();
         for (int i = 0; i < stringList.size(); i++) {
             String string = stringList.get(i);
-            stringList.set(i, string.replace(oldChar, newChar));
+            bookMeta.setPage(i, string.replace(oldChar, newChar));
         }
     }
 }