title: ADAL.NET v3 does not support AcquireToken with UserCredential?
body: <p>In ADAL.NET 2.x, we use the below code to acquire token from Azure AD using <code>UserCredential</code> and it works perfectly:</p>
  
  <pre><code> var authContext = new AuthenticationContext(Authority);
   var userCredential = new UserCredential(username, password);
   var token = authContext.AcquireToken(ResourceUrl, ClientId, userCredential);
  </code></pre>
  
  <p>When I upgraded ADAL.NET v3 today, the code cannot be compiled anymore because on the new version, <code>UserCredential</code> does not have overloaded constructor with username and password.</p>
  
  <p>How I can workaround this with the new version of ADAL.NET v3?</p>