title: ng build drops a ton of errors on a project which worked fine during development
body: <p>I've just finished my first own Angular project (applause), but when I try to deploy it, <code>ng build</code> throws a gazillion of errors. They are mostly about properties or values which do not exist, but it also has a problem with <code>private</code> variables.</p>
  
  <p>I am sure there must be a switch to ignore these errors, but which one is it?</p>