title: Make text labels span multiple ggplot facet grid panes
body: <p>How can <code>geom_text_repel()</code> labels be made to span multiple <code>facet_grid()</code> panes?  For instance, if there are many long labels that do not fit within the proper dimensions of each grid plot, the label should be positioned as if the <code>facet_grid()</code> were a single plot.</p>
  <p>For example:</p>
  <pre><code>df &lt;- data.frame(
    x = rep(1:3, 5), 
    y = runif(15), 
    label = paste0(&quot;very long label &quot;, 1:15), 
    group = do.call(c, lapply(paste0(&quot;group &quot;, 1:5), function(x) rep(x, 3)))
  )
  
  library(ggplot2)
  library(ggrepel)
  ggplot(df, aes(x, y, label = label)) + 
    geom_point() + 
    facet_grid(cols = vars(group)) + 
    geom_text_repel()
  </code></pre>
  <p><a href="https://i.stack.imgur.com/bhViu.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/bhViu.png" alt="Example of how to not label across facet grids" /></a></p>
  <p>If there is another way to group samples on the x-axis that would mimic a column-wise facet-grid, that's perfectly fine too. In my case, I need to group samples by a grouping variable (correspondingly labeled), and then within each group order them by a continuous variable.</p>