title: Add legend between patchwork main title and plot titles
body: <p>Is it possible to have legend below 'main' title' and above plot titles using patchwork?</p>
  <pre><code>library(ggplot2)
  library(patchwork)
  
  p1 &lt;- ggplot(mtcars, aes(disp, wt, color = factor(gear))) + 
      geom_point() + 
      labs(title = &quot;first plot title&quot;)
  p2 &lt;- ggplot(mtcars, aes(drat, qsec, color = factor(gear))) + 
      geom_point() + 
      labs(title = &quot;second plot title&quot;)
  
  (p1+p2) + 
      plot_layout(guides = &quot;collect&quot;) + 
      plot_annotation(title = &quot;main title&quot;) &amp; 
      theme(legend.position = &quot;top&quot;)
  </code></pre>
  <p><a href="https://i.stack.imgur.com/HNLtZ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/HNLtZ.png" alt="enter image description here" /></a></p>