introduce check type definition

ng2-components/config/webpack.common.js

@@ -4,6 +4,7 @@ const fs = require('fs');
 const path = require('path');
 const CopyWebpackPlugin = require('copy-webpack-plugin');
 var HappyPack = require('happypack');
+const ForkTsCheckerWebpackPlugin = require('fork-ts-checker-webpack-plugin');
 
 const alfrescoLibs = [
     'ng2-activiti-analytics',
@@ -132,6 +133,7 @@ module.exports = {
     },
 
     plugins: [
+        new ForkTsCheckerWebpackPlugin(),
         new HappyPack({
             id: 'ts',
             threads: 8,