title: How to get all projects in a SBT task?
body: <p>I'm writing a SBT task, which will get all projects of the whole project, then I can run some tasks against them.</p>
  
  <p>The pseudo code is like:</p>
  
  <pre><code>val projects = someTaskToGetProjects.value
  val updateReports = projects.map(p =&gt; (update in p).value)
  </code></pre>
  
  <p>But I can't find any task or setting to get the project list, how to do it?</p>