Bugfix: Move export to main library instead of example

tool/generate_example.dart

@@ -38,7 +38,6 @@ void main(List<String> arguments) {
     '',
     "import 'package:font_awesome_flutter/font_awesome_flutter.dart';",
     "import 'package:font_awesome_flutter_example/example_icon.dart';",
-    "export 'fa_icon.dart';",
     '',
     '// THIS FILE IS AUTOMATICALLY GENERATED!',
     '',

tool/generate_font.dart

@@ -52,6 +52,7 @@ void main(List<String> arguments) {
     '',
     "import 'package:flutter/widgets.dart';",
     "import 'package:font_awesome_flutter/icon_data.dart';",
+    "export 'fa_icon.dart';",
     '',
     '// THIS FILE IS AUTOMATICALLY GENERATED!',
     '',