fixes waitTimeout, waitDelay not working with float

build/docs/content/04-html.md

@@ -296,7 +296,8 @@ $client->store($request, $dest);
 ## Wait delay
 
 In some cases, you may want to wait a certain amount of time to make sure the
-page you're trying to generate is fully rendered.
+page you're trying to generate is fully rendered. For instance, if your page relies
+a lot on JavaScript for rendering.
 
 > The wait delay is a duration in **seconds** (e.g `2.5` for 2.5 seconds).
 
@@ -339,4 +340,4 @@ $request = new HTMLRequest($index);
 $request->setWaitDelay(5.5);
 $dest = "result.pdf";
 $client->store($request, $dest);
-```
+```