title: branch and checkout using a single command
body: <p>Creating and using a new branch involves two commands:</p>
  
  <pre><code>$ git branch new_branch_name
  $ git checkout new_branch_name
  </code></pre>
  
  <p>I tend to forget the latter, which can be annoying. Is there a way to do this using a single command? Perhaps using an alias, or something similar? I know I could write a shell function, but that seems a bit much work for such a simple and common task.</p>
  
  <p>Bazaar does support this to some degree using the <code>bzr branch --switch</code> notation.</p>