title: Join Multiple R Rastervis levelplots
body: <p>I have two rasterstacks, each with a common legend, that I want to put on a single plot with a space in between stacks. I want the raster images to be the same size within each block and across blocks. Is there an easy way to do this using <code>Rastervis::levelplot</code>. I believe the best way is too add a legend to <code>grid.arrange</code> object, as in this MWE</p>
  
  <pre><code>library(raster)
  library(rasterVis)
  s &lt;- stack(
  raster( matrix(runif(9),3,3)),
  raster( matrix(runif(9),3,3)) )
  
  gridExtra::grid.arrange(
  levelplot(s, colorkey=FALSE, at=seq(0,1,length.out=11)),
  levelplot(s, at=seq(0,1,length.out=11)),
  ncol=2)
  </code></pre>
  
  <p>An even simpler solution would be to do this from within a single leveplot call</p>