title: How to use github java API (org.eclipse.egit.github.*) to search for Users by Mail
body: <p>I'm using GitHub Java API (org.eclipse.egit.github.*) and I have to search for a specific Users to assign Issues. </p>
  
  <p>The problem is that I have to look for proper user by his/her <strong>mail</strong> and not with <strong>userid</strong>.</p>
  
  <p>I cannot see any Search method in UserService class... any advice please?</p>