title: Create a Pull Request as part of build step in VSTS
body: <p>We are using VSTS for our build server and for version control. </p>
  
  <p>As part of our build process I would like to create a Pull Request from <code>master</code> branch to <code>develop</code> branch (for build running on <code>master</code> only). 
  I know there is an <a href="https://www.visualstudio.com/en-us/docs/integrate/api/git/pull-requests/pull-requests#create-a-pull-request" rel="nofollow noreferrer">API endpoint</a> to do that. </p>
  
  <p>But I wonder if there is a better way to handle it? Like a custom step that does it (and I've missed it)?</p>