title: Submitting refs/drafts rejected by gerrit . But able to upload 'changes'
body: <p>I am trying to submit a draft change to our gerrit .But it fails with the following error.
  However , I am able to submit 'changes' ( patch sets ) successfully.</p>
  
  <pre><code>            &lt;~/build&gt; git push origin HEAD:refs/drafts/remote-branch
              Counting objects: 16, done.
              Delta compression using up to 8 threads.
              Compressing objects: 100% (13/13), done.
              Writing objects: 100% (13/13), 5.98 KiB, done.
              Total 13 (delta 3), reused 0 (delta 0)
              remote: Resolving deltas:   0% (0/3)
              To ssh://&lt;my-repo&gt;
              ! [remote rejected] HEAD -&gt; refs/drafts/remote-branch (prohibited by Gerrit)
              error: failed to push some refs to 'ssh://&lt;my-repo&gt;'
  
              &lt;~/build&gt; git push origin HEAD:refs/for/remote-branch
              Counting objects: 16, done.
              Delta compression using up to 8 threads.
              Compressing objects: 100% (13/13), done.
              Writing objects: 100% (13/13), 5.98 KiB, done.
              Total 13 (delta 3), reused 0 (delta 0)
              remote: Resolving deltas:   0% (0/3)
              To ssh://&lt;my-repo&gt;
              * [new branch]      HEAD -&gt; refs/for/remote-branch
              &lt;~/build&gt; 
  </code></pre>
  
  <p>Is there any option we need to configure to enable 'drafts' in Gerrit or configuring some user permissions ?</p>