title: Using Advanced Google Services with Service Account
body: <p>I am developing an application using Google Apps Script and using some Advanced Services such as Admin SDK (Directory API) and Reseller API.</p>
  <p>It seems like these API's are being called by my WebApp under context of user who is accessing my WebApp (it's deployed with 'Execute the app as 'User accessing the webapp').</p>
  <p>Ideally, I would like these API's calls to be authenticated with some Service Account under my project (in Dev Console). Is it possible? How?</p>