Merge pull request #1 from bertspaan/gh-pages

fixed typo

README.md

 
 var myLayer2 = L.tileLayer(...).addTo(map)
 
-L.Control.sideBySide(myLayer1, myLayer2).addTo(map);
+L.control.sideBySide(myLayer1, myLayer2).addTo(map);
 ```
 
 ### Example