Update README.md

Replace "handers" with "handlers"

README.md

@@ -62,7 +62,7 @@ If you are not using any of these frameworks, here's a very simple way to instal
     $whoops->register();
     ```
 
-For more options, have a look at the **example files** in `examples/` to get a feel for how things work. Also take a look at the [API Documentation](docs/API%20Documentation.md) and the list of available handers below.
+For more options, have a look at the **example files** in `examples/` to get a feel for how things work. Also take a look at the [API Documentation](docs/API%20Documentation.md) and the list of available handlers below.
 
 You may also want to override some system calls Whoops does. To do that, extend `Whoops\Util\SystemFacade`, override functions that you want and pass it as the argument to the `Run` constructor.