increase node heap memory for ng build

Author: HackbrettXXX

package.json

@@ -7,7 +7,7 @@
     "postinstall": "node -e \"require('fs').copyFileSync('../yFiles-for-HTML-Complete-2.2.0.3-Evaluation/ide-support/yfiles-typeinfo.js','./src/yfiles-typeinfo.js')\" && node -e \"require('fs').copyFileSync('../yFiles-for-HTML-Complete-2.2.0.3-Evaluation/lib/license.json','./src/license.json')\"",
     "ng": "ng",
     "start": "ng serve",
-    "build": "ng build",
+    "build": "node --max_old_space_size=4096 node_modules/@angular/cli/bin/ng build",
     "test": "ng test",
     "lint": "ng lint",
     "e2e": "ng e2e"