update README.md

README.md

@@ -18,7 +18,7 @@ To use this plugin, add `flutter_icons` as a [dependency in your pubspec.yaml fi
 import 'package:flutter_icons/flutter_icons.dart';
 import 'package:flutter/material.dart';
 
-Icon(icon:Ionicons.ios_search);
-Icon(icon:AntDesign.stepForward);
+Icon(icon:Ionicons.getIcon("ios-search"));
+Icon(icon:AntDesign.getIcon("stepforward"));
 ```
 ##### More Icons will be added later , welcome everyone to contribute code.

lib/flutter_icons.dart

@@ -3,3 +3,4 @@ library flutter_icons;
 export 'ionicons.dart';
 export 'ant_design.dart';
 export 'font_awesome.dart';
+export 'material_icons.dart';